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Sri Lankan pioneering superconductivity research

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Prof Ranga Dias and team make world’s first-ever room-temperature superconductor

By Sajitha Prematunge

It is not a vaccine for COVID-19, but it could be the next best thing. The world’s first superconductor at room temperature, developed by a research team lead by Sri Lankan born physicist, Prof. Ranga Dias at the University of Rochester, USA, could potentially revolutionise everything from transport to energy industry.

The team recently discovered carbonaceous sulphur hydride (CSH), a new compound that acts as a superconductor at 15 °C at a pressure of 267 Giga Pascals (Gpa), or 2.6 million atmospheres (75 percent of the pressure at the earth’s core). The heady article in Nature magazine, which published this groundbreaking discovery in its cover story on October 15, may sound gobbledygook for some. Consequently, The Island interviewed University of Rochester, USA, Department of Physics and Astronomy and Department of Mechanical Engineering, Assistant professor Prof. Ranga Dias; Ph.D. student in Physics, Hiranya Pasan and Ph.D. candidate in Optics, Ashan Ariyawansa to put things in perspective.

A superconductor is a materiel that poses no electrical resistance. “We used two diamonds, each approximately 150 to 200 micron in diameter, on top of each other, to make what’s called a diamond anvil cell. The sample was sandwiched between the two diamonds and pressure applied.” Pasan explained that they could achieve pressures of up to 500 Giga Pascals with the diamond anvil cell. “For comparison, that’s more than the pressure at the earth’s core,” said Pasan. “The diamond anvil cell acts as a materiel search engine, that we use to test material at different pressure until we found the ideal conditions to achieve superconductivity for each material, allowing us to determine which materiel is the most effective. And the result was CSH, a compound belonging to a new class of dense hydrogen rich material.

 

What took so long?

Even though their work was based on old theory, in existence for more than a century, there is still a lot of unknowns. “Even established theory does not explain the mechanism that goes into the making of a superconducting material,” said Dias. But they had two criteria going for them, the ideal superconductor should be of a lighter element that can make stronger bonds. This was the basic premise under which Dias and his team started working with carbon and sulphur. “Our success depended on the right elemental combination,” said Dias, a researcher on high-pressure physics, who had been working with carbon and sulfur for just over a decade.

Pressure variations can convert basic elements of the periodic table into something completely different. Dias explained complex high-pressure physics with a simple analogy. There are two people in a room who can’t interact with each other because they are on opposite corners of the room. Now have the walls close in on them until they are able to talk, shake hands and interact. “The same principle can be applied to elements. When pressurized, atoms and molecules become more interactive and make new bonds. This alters the actual chemical nature of the compound. That’s the beauty of high-pressure physics, it allows you to manipulate the identity of compounds to create whole new material with completely unexpected properties,” said Dias.

 

Previous research

Dias holds a Bachelor of Science degree from the University of Colombo. He turned his attention to metallic hydrogen research as an extension of his PhD research on high-pressure physics at the University of Washington. In 2017, Dias, then a postdoctoral fellow at Harvard University and Isaac Silvera, physicist at Harvard announced the discovery of metallic hydrogen in the Science magazine. Their experiment involved compressing hydrogen gas, which liquifies when cooled to minus 423 degrees Fahrenheit (minus 252.778 Celsius), and then solidifying it at lower temperatures. The claim came under heavy criticism for being based on a single observation, on reflectivity (an expected signature of metallic hydrogen), and without a direct measurement of the pressure involved. The original ‘metallic hydrogen’ sample was lost during the subsequent failure of the diamond anvil cell. Prof. Dias said: “It was a complete study. What is left is to describe the properties of metallic hydrogen, which we are actively working on. Research takes time. None of these experiments are easy.” He joined the University of Rochester, in 2017 as a professor, and is currently conducting further research on metallic hydrogen. He further explained that the Harvard group measured the pressure directly using standard methods that any high-pressure scientist used. Every high-pressure experiment ended with the failure of the diamond anvil cell, which means the loss of the sample. Consequently, Dias argued that there was nothing unusual about the fact that their diamond broke, resulting in the loss of the sample. “I think fellow competitors who were trying to make metallic hydrogen wasn’t happy that we got it right, their criticism has nothing to do with science but rather was a political attack on my previous advisor [Silvera].”

When asked how positive he is about the newly discovered carbonaceous sulphur hydride, in light of the previous backlash, Dias said that he doubted there was a connection. “They are two different experiments and very different samples. The hallmark of superconductivity is the complete absence of electrical resistance. And another property of superconducting materials is that when it is cooled below the superconducting transition temperature, the magnetic field lines are expelled from the material. We have observed both of these key properties on our carbonaceous sulphur hydride materials at high pressures.” Dias confident of the results.

Prof. Dias’ finding has definitely sparked investor interest. In fact, investors are already lining up to fund a research company, by the name of ‘Unearthly Materials’, set up under the leadership of Prof. Dias to carry out further research and to manufacture superconductors on a large scale. A financial capital of US $ 2 million, has already been provided by investors. Dias hopes it will culminate in a highly productive venture in three to five years.

 

Implications

Prof. Dias believes that the technology could open up a world of possibilities for medical imaging such as MRI, computing and consumer electronics such as mobile phones. Applications of his discovery include low-cost MRI scanners, magnetic levitation trains, and power lines with no electrical resistance. “A computer, for example, has a heavy cooling system with heat sink, fans and the like, but with a superconductor none of these will be necessary,” explained Hiranya Pasan, who was tasked with low temperature analysis in this research. With this kind of tech everything from car radiators to train tracks could become redundant. “A huge amount of energy is lost in transmission per year. It adds up to a lot of money,” pointed out Pasan. So, if someone were to mass produce superconducting wire, which offers no electrical resistance, he would save billions of or dollars for countless governments.

And then there is the Meissner effect, which in layman’s terms means to repel a magnet. Superconductors are strongly diamagnetic and expel magnetic fields. As such trains could employ magnets that levitate on superconducting material. “It produces no friction,” explained Pasan. Such frictionless high-speed trains could revolutionise the transport sector.

“The technology already exists,” explained Dias. Superconducting technology is used in MRI scanners, particle accelerators, and magnetic levitation trains of experimental scale in Japan, all of which involves large magnetic fields. “But it requires cryogenics.” Meaning that some metals reach superconductivity at extremely cold temperatures and, therefore, have to be cooled to about 10 to 20 Kelvin. For context, that’s minus 263.15 to 253.15 Celsius. The critical temperature of the first superconductor, discovered in 1911, was minus 269 °C, and the fact that no research has ever been able to find a material that acts as a superconductor in room temperature has been one of the major challenges in physics.

“The cryogenic factor is what makes the technology so expensive and therefore economically unviable,” pointed out Dias. So, if cryogenics were to be taken out of the equation, it would make medical imaging, for example, much more affordable and efficient. Prof. Dias explained that liquid helium is the most widely used coolant in superconducting applications, a resource fast diminishing.

He and his team were able to take the cryogenics out of the equation, but maintaining such gargantuan pressures make mass production of superconducting material virtually impossible. When asked how stable the new compound was Dias explained that CSH could be metastable, meaning that it may not revert to the original compound of carbon and sulphur once pressure is relieved. If not, it’s back to square one for the team as they would have to find another compound that acts as a superconductor at both room temperature and atmospheric pressure. The team revealed that they would conduct the ultimate experiment by relieving pressure, in the weeks to come, which Pasan has been tasked with. “Once we have a metastable superconducting material at ambient pressure, it’s just a matter of replicating it, using techniques like chemical deposition and Molecular-beam epitaxy (MBE), to achieve mass production.” Those were the standard techniques and therefore were affordable, he said.

Ground-breaking discoveries are made every few decades in the western world and they have little or no effect at all on developing nations such as Sri Lanka. So why is a superconductor at room temperature even significant for a country like Sri Lanka? “I don’t think that the GDP matters in terms of implications of such discoveries, said Dias. “What is rocket science is developing a superconductor at room temperature. When that’s a reality, application comes easy. Whether it was frictionless trains or MRI scanners, such technology can always be applied by replacing the existing technology with the new.”

 

Application of such technology in quantum computing would be difficult for a country like Sri Lanka, but Dias pointed out that the implications of the technology for energy transmission was of considerable significance to developing countries. As Pasan pointed out, a lot of electricity is lost during transmission. Dias argued that with a superconducting wire, that pose no resistance, third world power generation can be made more efficient, thereby increasing capacity. “This kind of application is not difficult to apply even in a developing country.” Dias assured that such technology would be affordable even for developing countries.

 

Local students

When asked about the practical difficulties Sri Lankan students have to face, Hiranya pointed out that as opposed to Sri Lanka, the US has a more student-centred education system, while Dias said there was a clear lack of enthusiasm for research in Sri Lanka. “During my time in Sri Lanka, we were hardly exposed to experiments, we rarely saw instruments, except at practicals during undergraduate years, simply because we didn’t have the facilities,” said Prof. Dias. “The system is exam-oriented, and as a result we lacked hands on experience.” Dias pointed out that in the US education system there was ample opportunity for research. “Even the exam questions here are very practical. It hones critical thinking instead of promoting memorising equations and just getting good grades.” Such a system increases research productivity, he said.

“Research lacks support in Sri Lanka, especially in terms of funding,” said Dias. “In the States we can acquire federal, corporate and other sources of funding. But in Sri Lanka we don’t have that kind of a mechanism.”

But things are looking up, said Ariyawansa. “Collaborative research on chemistry and biotechnology is undertaken increasingly in Sri Lanka,” he said, pointing out that industrial chemistry and nanotechnology were fast developing areas, but he admitted that physics was still lagging behind. “We now have institutions such as SLINTEC [Sri Lanka Institute of Nanotechnology], which has succeeded in attracting a lot of expatriate academics back into the country,” added Dias. He opined that such infrastructural support and funding would facilitate cutting-edge research.

When asked whether such cutting-edge research would have any practical applications in Sri Lanka and whether putting so much money and effort into research was viable in the absence of practical applications, Prof. Dias said that there would always be opportunities in terms of putting research into practice. “Commercial production of graphene by SLINTEC is a case in point. It’s a direct application. I’m sure that if Sri Lanka can produce high grade graphene, we can export it. Graphene has a lot of applications, especially in electronics. It’s used widely in the US, Japan, Europe and South Korea for semiconductor and mobile applications.”

The same principle can be applied to diamonds. “With the right combinations of material diamonds can be grown in the lab,” Dias pointed out that this could revolutionise the diamond industry. “This is already being done in the US,” said Dias, reiterating that material research would always have applications.



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Why record export earnings may not be good news

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By Gomi Senadhira

The press release by the Central Bank on the external sector performance ,in June 2022, perhaps was the first piece of good news we had received for a long time. According to the press release, “Earnings from merchandise exports, in June 2022, increased by 23.9 percent over the corresponding month, in 2021, recording US dollars 1,248 million, which is the highest ever monthly export earnings recorded. An increase in earnings of both industrial and agricultural exports contributed to this favourable outcome, …. Cumulative export earnings, from January to June 2022, also increased by 14.3 percent, over the same period in the last year, amounting to US dollars 6,514 million.” So, most of us would think we have enough dollars to cover our essential imports. But, apparently, that is not the case.

Earlier, the Central Bank Governor, Dr. Nandalal Weerasinghe, had said that exporters only converted about 20% of their export earnings into Sri Lankan Rupees and the rest was not brought back to Sri Lanka. That amounts to the US $800 million a month! The Governor had also said “… At least 40% of the total export earnings should be added to the formal financial system of the country. So exporters have a responsibility, at a very difficult time like this, to bring back their foreign exchange, through the banking system, and if that happens, then we can resolve the fuel crisis comfortably.”

(Diesel shipment that arrived in Colombo, on 16 July, still not paid for want of dollars – The Island July 30th) It appears as if the Governor is pleading with the exporters to bring back at least 40% of their export earnings. More notably, from Dr Weerasinghe’s statement, it is clear that the exporter had only converted 20% of their export earnings to rupees during the last five months. Did they convert their export earnings to rupees during the last year, or in the previous years? For how long has this been going on? When the Central Bank says “… exporters have a responsibility, at a very difficult time like this, to bring back their foreign exchange, through the banking system,” does that mean the foreign exchange earned, with the exports, is brought through the hawala network, or other similar arrangements?

Exporters deserve credit for the great service they provide and should be rewarded, appropriately. But not disproportionately. The export earnings are not earned by the exporters alone. These earnings are earned by all those who contribute to manufacturing the export products. All of them should be getting their fair share of the export proceeds. If not, there is something terribly wrong with the system. Is this normal in international trade?

During the last few years, some of the studies by Indian scholars, including Utsa Patnaik and Shashi Tharoor, have placed in the public domain some of the less known facts on the effects of the British colonial rule on India. They explain how the British seized India, “… one of the richest countries in the world – accounting for 27% of global GDP in 1700 – and, over 200 years of colonial rule, reduced it to one of the world’s poorest,” and how during the period British Raj siphoned out $45 trillion from India.

How was this done? Patnaik explains, “In the colonial era, most of India’s sizeable foreign exchange earnings went straight to London—severely hampering the country’s ability to import machinery and technology in order to embark on a modernisation path, similar to what Japan did in the 1870s. …, a third of India’s budgetary revenues was … set aside as ‘expenditure abroad’. The secretary of state (SoS) for India, based in London, invited foreign importers to deposit with him the payment (in gold and sterling) for their net imports from India, which disappeared into the SoS’s account in the Bank of England. Against these Indian earnings he issued bills… to an equivalent rupee value—which was paid out of the budget, from the part called ‘expenditure abroad’.” Patnaik underlines that this was “something you’d never find in any independent country,”

But it appears something very similar is happening in Sri Lanka, many years after the independence! If the exporters do not “bring back their foreign exchange ,through the banking system,” or only bring back 20% of it, then how do they pay for goods and services obtained locally? The local value addition for most of our exports is 70% to 80% or higher! The only major exception is cut and polished diamonds. Tea exporters buy tea with rupees. Some of the imported inputs, like fertiliser, or diesel, are sourced locally! The garment industry had moved up the value chain during the last 40 years and provide many value-added services, like designing, locally.

How do the exporters pay for all these goods and services, if they keep more than 60% of their export earnings outside the country? Do they get it through “hawala” or similar arrangements? During the British Raj, payments to local producers were done with the taxes collected by the Raj. In present-day Sri Lanka, how does one manage to raise a large amount of cash to operate such a system?

If a sizeable chunk of Sri Lanka’s foreign exchange earnings goes straight to banks in London, New York, Zurich, or elsewhere, severely hampering the country’s ability to import essential items, doesn’t that mean, Sri Lanka’s wealth is getting siphoned out through our exports? And there is not much of a difference between what happened during the colonial period and the post independent Sri Lanka!

So, June’s record export earnings also mean nearly US$ billion was siphoned off during the month! A new record for the month of June! And that means Patnaik was wrong when she said this was not “something you’d never find in any independent country”

That is not good news.

(The writer is a specialist on trade and development issues and can be contacted at senadhiragomi@gmail.com)

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Improving trend needs to be sustained on multiple fronts

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by Jehan Perera

The government appears to have secured political stability in the short term.  So far President Ranil Wickremesinghe’s efforts to restore stability appear to be working. Political stability is necessary for decisions to be made and kept.  It is a necessary element for international support to come in.  One of the IMF’s conditions to provide the country with the multi-billion-dollar loan it seeks is political stability that would ensure that commitments that are made will be kept.  The protest movement has not mobilised public demonstrations on the very large scale of the past after the appearance of Ranil Wickremesinghe in leadership positions, initially as prime minister and subsequently as president. This would be seen as an achievement by the government.  The present governmental line that protests should be within the law is difficult, and also frightening, to challenge when a state of emergency is in force.

The government has shown its ability to wield the emergency law with deterrent effect. Under the state of emergency that President Wickremesinghe declared on July 18, the period that a person may be detained before being brought before a magistrate has been increased from 24 to 72 hours. The authorities have been granted additional powers of search and arrest, and the military has been empowered to detain people for up to a day without disclosing their detention. The state of emergency also gives the president and the police broad powers to ban public gatherings, allows the police or military to order anyone to leave any public place or face arrest, and makes it an offense to cause “disaffection” or to spread “rumours.” However, in a sign that Sri Lanka’s system of checks and balances is still working, the Colombo Chief Magistrate’s Court has rejected a request by the police to ban a public protest planned by political parties and multiple organisations on September 9.

Human Rights watch has pointed out that “these provisions are vague, overly broad, and disproportionate in violation of the rights to freedom of expression, peaceful assembly, association, and movement.”  The midnight strike on the protestors who had camped for over three months at the main protest site at Galle Face would make any reasonable person think twice before getting into physical confrontation with the government.  The social media coverage of events that night showed men in black uniform and wearing masks, attacking the unarmed protestors.  As these men did not wear identification badges, there is a question whether they were part of the official security forces or drawn from other groups that work with them.  This response brought discredit to the perpetrators and disturbed both Sri Lankan people and the international community that have the welfare of Sri Lanka at heart.

The government has also used the full power of the draconian law to ensure that the leadership of the protest movement is neutralised. Several of them have been arrested, some of them given bail, others remanded, which would send a chilling message to the others.  The government has also shown its willingness to offer high positions to those who are prepared to join it.  This has led to a situation where two trade union leaders active in the protest movement have been treated very differently.  One has been offered a high post while the other has been put into prison, although he has now been given bail.  In a signal that he is sensitive to public pressure and human rights concerns, President Wickremesinghe had spoken to leader of the Ceylon Teachers Union, Joseph Stalin, after he was remanded and reportedly said he admires the members of the protest movement who talk of a system change.

ECONOMIC STABILISATION

Apart from the appearance of political stability there is also the appearance of economic stabilisation.  The shortages of cooking gas, petrol and diesel, and the 13-hour power cuts were among the main catalysts of the protest movement.  It was during the period of long power cuts, when staying at home became unbearable, that neigbourhood groups began to converge in urban centres to hold candlelight protests.  However, at this time the supply of gas, petrol and diesel has improved significantly and the kilomere-long lines in front of fuel stations are much less common.  Credit has gone to the QR code system put in place that gives to each vehicle a weekly quota.

The challenge for the government is to ensure that the economic situation continues to be stable without experiencing the acute shortages of key items that causes distress to the general population.  The QR code system can only work if there is petrol and diesel to be distributed.  The current imports of cooking gas, petrol and diesel appear to have been made possible by a World Bank loan which was re-purposed to the purchase of essential items.  However, these funds will dry up soon.  The question is what will happen after that.  There is apprehension that the country will fall once again into a situation of severe shortage.  The government needs to take the people into its confidence regarding the future.  The government also needs to be trusted if it is to be believed.

The World Bank has given an indication that they are still to be convinced regarding the provision of further assistance to Sri Lanka.  Earlier this month, the World Bank issued a statement “expressing deep concern about the dire economic situation and its impact on the people of Sri Lanka yesterday said it does not plan to offer new financing to Sri Lanka until an adequate macroeconomic policy framework is in place.  Issuing a statement, the World Bank Group said it is repurposing resources under existing loans in its portfolio to help alleviate severe shortages of essential items such as medicines, cooking gas, fertiliser, meals for school children and cash transfers for poor and vulnerable households.  To date, the World Bank has disbursed about US$160 million of these funds to meet urgent needs.”  This is extremely concerning as the World Bank is closely connected to the IMF on which Sri Lanka is pinning its hopes for a big loan.

POLITICAL STABILITY

The issue of political stability is highlighted by the government as being necessary to obtain international assistance and also as a justification for quelling the protest movement through emergency laws.  There is explicit blame being apportioned to the protest movement for creating instability in the polity that is deterring the influx of foreign assistance and investments.  However, the fuller picture needs to be seen.  The IMF as much as the World Bank, and indeed other potential sources of donor support, want their resources to be used for the intended purpose and not be squandered or siphoned away corrupt practices and in sustaining loss-making state institutions.

The hoped-for IMF-supported programme to provide assistance to Sri Lanka is being developed to restore macroeconomic stability and debt sustainability, while protecting the poor and vulnerable, safeguarding financial stability, and stepping up structural reforms to address corruption vulnerabilities and unlock the country’s growth potential. IMF mission team to Sri Lanka last month specifically mentioned the need to reduce corruption stating that “Other challenges that need addressing include containing rising levels of inflation, addressing the severe balance of payments pressures, reducing corruption vulnerabilities and embarking on growth-enhancing reforms.”

Both the international funding agencies and the protest movement are on the same page when it comes to opposing corrupt practices.  The main slogans of the protest movement during their heyday was the ouster of the then president, prime minister and cabinet of ministers, and indeed the entire parliament, on account of the corruption that they believed was responsible for having denuded the country of its foreign exchange reserves. This was not simply the replacement of one set of corrupt leaders by another. There are disturbing signs that some of those accused of corruption are once again on the ascendant.

The underlying demand of the protest movement was and continues to be the very “systems change” that the president has said he admires in his reported discussion with remanded trade union leader Joseph Stalin. Civil disobedience to obtain a government that is transparent and law abiding, that does not steal the wealth of the country, is a noble goal, no less sacred than the civil disobedience struggles engaged in by Mahatma Gandhi in India and Martin Luther King in the United States.  The ingredients for a rebound of the protest movement continue to be in place and hopefully the evidence of a systems change will become more convincing.

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Brenda Mendis… ‘Gindara Kellek’

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I first got to know Brenda Mendis when she was very much a part of the group Aquarius, before joining Mirage..

With Aquarius, her dynamism bloomed, on stage, when she partnered two other female vocalists – from the Philippines.

And…yes, they certainly did rock the scene; the three girls were the talk-of the-town and they were featured at some of the best venues in the city.

She was also, at one time, associated with the band 2Forty2.

Brenda now operates with an outfit called C Plus Band, and with whatever free time, that comes her way, the talented artiste is now working on originals.

The latest is the song ‘Gindara Kellek’ and this is what Brenda has to say:

“I have known this guy Chathurangana de Silva for a very time and he has been involved in composing certain songs for the C Plus Band.

“We then got down to discussing about putting together a song which could be classified as a fast genre in music, and Chathurangana, along with Sampath Fernandopulle, came up with the suggestion for the lyrics, and they did so, based upon a proper observation of my lifestyle and the personality portrayal of myself, and that’s how “Gindara Kellek’ came into the scene.”

Brenda went on to say that the composing was done during a tight schedule.

“As I am the female vocalist, on a full time basis, with the C Plus Band, it took us more time than what is usual spent at a recording session, because of our public performances.”

‘Gindara Kellek’ is not Brenda’s maiden effort. She has been involved in quite a few other originals, including ‘Tharu Peedena Seethale,’ ‘Obai Mage Thaththe,’ ‘Mage Raththaran,’ ‘Kaprinna (Chooty),’ ‘You Never Know,’ ‘Mea Nilwan Nimnaye, and ‘Sitha Igilee Gihin.’ And, they are all uniquely different to each other, she says.

With the country going through a tough period, Brenda, spends her free time working out and reading.

“I would take this opportunity, through your very popular music page, to thank all those who helped me throughout my journey in this wonderful field of music.

“I shall continue to keep music lovers happy, with my music, and I would also thank my followers for supporting me and for being with me throughout my career in showbiz.”

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