Quantum Information Processing

The realization of a scalable quantum information processor requires the ability to interface stable quantum memories with reliable quantum channels. However, what makes for an ideal quantum storage device (e.g. isolation) is typically not what makes for an ideal quantum wire. This dichotomy naturally points to a hybrid-systems approach. For instance, NV spin qubits can act as quantum RAM in an architecture where the wiring is provided by superconducting resonators. The low-temperatures required for superconducting systems impose new constraints on the (typically) ambient-temperature NV memory, while also suggesting the possibility for novel coupling protocols. In particular, at liquid Helium temperatures, one can access the electronic excited state of the NV and make use of the strong electric dipole moment for enhanced interactions. Alternatively, for an engineered NV array, low-temperatures may enable the use of a chiral edge mode for dissipation-less quantum state transfer. Our group is broadly interested in hybrid architectures for quantum information processing.

Looking forward, strongly-interacting, disordered spin systems in the many-body localized phase may provide an alternative platform for realizing a quantum computer wholly orthogonal to the traditional pursuit of isolated qubits. The slow-growth of entanglement in the MBL phase implies a relatively long dephasing time-scale. This suggests that quantum information stored in such many-body localized states could be extremely robust to decoherence. However, two main challenges remain: (1) to devise an encoding scheme that can quickly and coherently prepare such a disordered many-body qubit and (2) to find a method which enables efficient quantum gates between spatially separated MBL-qubits. On the flip-side, the language of quantum information may provide a way to better define and characterize many-body localization.

 

Recent Publications

  1. Many-body localization protected quantum state transfer. Norman Y. Yao, Chris R. Laumann and Ashvin Vishwanath, arXiv:1508.06995.

  2. Quantum Control of Many-body Localized States. Soonwon Choi, Norman Y. Yao, Sarang Gopalakrishnan and Mikhail D. Lukin, arXiv:1508.06992.

  3. Topologically Protected Quantum State Transfer in a Chiral Spin Liquid. Norman Y. Yao, Chris R. Laumann, Alexey V. Gorshkov, Hendrik Weimer, Liang Jiang, J. Ignacio Cirac, Peter Zoller and Mikhail D. Lukin, Nature Communications 4, 1585 (2013).

  4. Scalable Architecture for a Room Temperature Solid-State Quantum Information Processor. Norman Y. Yao, Liang Jiang, Alexey V. Gorshkov, Peter C. Maurer, Geza Giedke, J. Ignacio Cirac, Mikhail D. Lukin, Nature Communications 3, 800 (2012).