CQT undergraduate research scoops University award for third consecutive year

The National University of Singapore recognises up to 15 undergraduate projects each year for excellence, bestowing on successful students the "Outstanding Undergraduate Researcher Prize" (OURP). The outstanding undergraduate researchers for the 2010-2011 academic year were announced in July, and for the third consecutive year a student who carried out their project at CQT is among the individual winners.

Le Phuc Thinh (pictured right) was awarded the prize for his project "Reference frame independent quantum key distribution with qudits". He was supervised by Valerio Scarani, who is a Principal Investigator at CQT and an Associate Professor in the NUS Faculty of Science, and Lana Sheridan, a CQT Research Fellow in Valerio's group. "Receiving the award is an absolute honour and an affirmation of the hard work and effort from me and my supervisors," says Thinh in his testimonial.

Quantum key distribution is a protocol for secure communication. In reference frame independent implementations, the two communicating parties do not need to align their communication devices. Thinh's project extended an existing protocol of this sort from qubits to qudits – from quantum bits (only two distinguishable states) to quantum "dits" (any number d of distinguishable states) – making the protocol faster and more robust with respect to noise or attacks. The result will be written up for submission to a peer-reviewed journal.

Undergraduate research projects are typically carried out over two terms. Thinh, who put in a year's groundwork studying at CQT in his spare time before starting his project, spent his first semester puzzling over the problem but making little progress. "It was quite dangerous for me," says Thinh. However, in his second term, he says "there was an 'aha' moment when I found a technique while browsing a textbook that could help me run the proof." Thinh has been bitten by the research bug and, starting 1 July, has joined Valerio's group as a PhD student.

Past CQT winners of the OURP have done equally serious research. In the 09-10 academic year, physics major Thiang Guo Chuan was named an outstanding undergraduate researcher after completing a research project under the supervision of Berge Englert, CQT Principal Investigator and NUS Professor. His project, "Optimal Lewenstein-Sanpera Decomposition of two-qubit states", addressed the question 'How quantum are qubit pairs?' and earned him sole-authorship of a paper, Phys. Rev. A 82, 012332 (2010). The previous year, Cai Yongqin Raymond, supervised by Valerio, won the award for "Finite Key Analysis for Quantum Cryptography". This work was published as New J. Phys. 11, 045024 (2009), with Raymond as first author.

NUS undergraduates interested in doing their final-year research project at CQT should contact the Principal Investigator(s) in their field(s) of interest. Students from other universities can apply for internships in the same way.