Raymond Laflamme

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Raymond LaflammeProfessor

Office: PHY 368
Phone: (519) 888-4567 ext. 33252, 32430
Email: laflamme@iqc.ca

Research interests

  • Quantum information theory and experiments
  • Quantum computing
  • Quantum control
  • Quantum simulations
  • Quantum gravity
  • Cosmology

Research activities

Information processing devices are pervasive in our society; from the 5 dollar watches to multi-billions satellite network. These devices have allowed the information revolution which is developing around us. It has transformed not only the way we communicate or entertain ourselves but also the way we do science and even the way we think. All this information is manipulated using the classical approximation to the laws of physics, but we know that there is a better approximation: the quantum mechanical laws. Would using quantum mechanics for information processing be an impediment or could it be an advantage? This is the fundamental question in the field of quantum information processing (QIP). QIP is a young field with an incredible potential impact reaching from the way we understand fundamental physics to technological applications.

In late 1994,after hearing of Shor's quantum factoring algorithm, I quickly realized that quantum computers would be hampered by the lost of quantum coherence (i.e. decoherence). In fact if decoherence is not taken care of, quantum computers lose their power. After the seminal work of Shor and Steane my colleague Manny Knill and I laid down mathematical foundation of quantum error correcting codes. With colleagues Miquel,Paz and Zurek, I have also discovered the most compact quantum error correcting code which correct one quantum error (more recently, with Knill, Negrevergne and Martinez, we implemented this quantum error correcting code using NMR). After having looked at error correcting codes my attention turned to taking care of errors which would happen while we are trying to correct errors. This lead to the threshold accuracy theorem which says that it is possible to compute a long a desired with given accuracy with reasonable (polynomial) amount of overhead as long as the error rate is below a threshold. It is an important discovery as it shows that imperfection and imprecision of realistic devices are not fundamental objections to quantum computing. A few year later, using the multi-disciplinary characteristic of Los Alamos National Laboratory, I learned how to use Nuclear Magnetic Resonance (NMR) and collaborated with NMR spectroscopists both at Los Alamos and MIT to to better undertand quantum information in an experimental setting. This work was ranked amongst the Top Ten Breakthroughs of the Year from the journal Science in 1998. The thread in my research has been to understand the limitations, both in theory and in experiments, on the control we have on quantum systems.

At present, my attention is focused on:

  • Theoretical methods for error control in quantum devices
  • Use of quantum computer to simulate quantum systems
  • Experimental implementation of small quantum information processing devices
  • Investigations of optical systems including linear elements, single photons source and detectors for quantum information processing devices

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