NTT Basic Research Laboratories Theoretical quantum physics research group
NTT Basic Research Laboratories Theoretical quantum physics research group
NTT Basic Research Laboratories Theoretical quantum physics research group

Message

Quantum theory is the basis of modern physics and explains the nature and behaviour of matter and energy at the atomic level. Its peculiar features, such as superposition and entanglement, open up the possibility of completely new ways to manipulate information. Quantum entanglement, for instance, is the phenomenon in which the state of composite systems can never be expressed by whatever collection of the descriptions of the subsystems. It is believed to be essential for achieving classically intractable applications such as quantum communication and computation. Our group working closely with experimentalists explores such quantum natures and how they can be applied to generate new forms of quantum technology.

Our topics of interest include:

  • Foundational aspects of quantum theory including randomness and nonlocal phenomena
  • The quantum internet
  • Quantum computation and simulation
  • Hybrid quantum systems

Selected publications

  1. K. Azuma, S. E. Economou, D. Elkouss, P. Hilaire, L. Jiang, H. K. Lo, I. Tzitrin, Quantum repeaters: From quantum networks to the quantum internet, Reviews of Modern Physics 95 (4), 045006 (2023).
  2. K. Azuma, S. Subramanian, G. Kato, Do Black Holes Store Negative Entropy?, Progress of Theoretical and Experimental Physics 2025 (5), 053A01 (2025).
  3. V. M. Bastidas, S. Zeytinoğlu, Z. M. Rossi, I. L. Chuang, W. J. Munro, Quantum signal processing with the one-dimensional quantum Ising model, Phys. Rev. B 109, 014306 (2024).
  4. V. M. Bastidas, Topological Thouless pumping in arrays of coupled spin chains, Phys. Rev. B 106, L220308 (2022).
  5. T. Hatomura, K. Takahashi, Controlling and exploring quantum systems by algebraic expression of adiabatic gauge potential, Phys. Rev. A 103, 012220 (2021).
  6. T. Hatomura, Shortcuts to adiabaticity: theoretical framework, relations between different methods, and versatile approximations, Journal of Physics B: Atomic, Molecular and Optical Physics 57, 102001 (2024).
  7. L. Ruks, K. E. Ballantine, J. Ruostekoski, Negative refraction of light in an atomic medium, Nature Communications 16, 1433 (2025).
  8. L. Ruks, X. Xu, R. Ohta, W. J. Munro, V. M. Bastidas, Coherent response of inhomogeneously broadened and spatially localized emitter ensembles in waveguide QED, Phys. Rev. A 109, 023706 (2024).
  9. T. Yamazaki, K. Azuma, Linear-optical fusion boosted by high-dimensional entanglement, Phys. Rev. Lett. 134, 200801 (2025).

Contact Information

Please visit NTT Basic Research Laboratories website.