Quantum Information & Computation, Quantum Optics, and Condensed Matter

Research Overview

My field of interest is Quantum Information & Quantum Computation and its intersection with Condensed Matter Physics and Quantum Optics (light-matter interaction). I am primarily interested in foundations of quantum theory, correlations (entanglement), open systems & decoherence, near term quantum algorithms and protocols, architecture of quantum computing (via graph theory and distributed approach) and realization of quantum information processing (QIP) via cavity/circuit-QED, ion traps, and topological matter. Condensed Matter aspects such as correlated quantum matter, magnetism in quantum theory and many-body systems also concern my interest. Quantum optics aspects of my interests include light-matter interaction which is very well exploited for QIP via cavity-QED theory, and measurements in quantum optics. More details topic-wise is given below.

Quantum Information and
Quantum Computing
  • Architecture of quantum computers, especially the approach of distributed quantum computing. Alternative approaches in monolithic architectures using graph theory (perfect transfer schemes and architectures)
  • Quantum Error Correction (QEC) protocols (general correction codes, topological codes, surface codes, etc.) for near term NISQ (Noisy Intermediate Scale Quantum) quantum computers
  • Theory of entanglement and general correlations for many-qubit system and mixed states, and entanglement purification
  • Quantum Communication over noisy channels
  • Development of quantum algorithms for problems in linear algebra (hybrid quantum-classical and variational algorithms) for near term devices and long term scalable quantum technology
  • Quantum programming, testing, and benchmarking in variety of platforms and hardware implementations (IBM Qiskit, Rigetti systems, Xanadu Pennylane, Microsoft Q#, IonQ, and adiabatic annealer(s) – DWave)
  • [Learning] Quantum Machine learning and advanced numerics for large scale simulations
Quantum Optics
  • Light matter interaction over different coupling regimes (Jaynes-Tavis-Cummings, approximations, strong and ultrastrong coupling)
  • Cavity quantumelectrodynamics (Cavity-QED) and Circuit-QED (superconducting qubit architecture)
  • Open Quantum Systems (Master Equations, Lindbladian, Quantum Langevin Equations (QLEs)) in Markovian and non-Born-Markovian systems
  • Design of superconducting quantum circuits (SQCs) and scalable architecture with waveguide-QED systems (including chiral quantum networks)
  • Input/Output theory in circuit-QED
  • Theory of quantum decoherence in complex quantum systems
  • Ion-trap theory and quantum optics of the QIP implementation with NV-centre

Condensed Matter
  • Topology in condensed matter systems (Quantum fractional Hall effect and further)
  • Quantum Annealing (QA) with Ising and Heisenberg models with various coupling and connectivity configurations
  • Quantum many-body physics
  • Magnetism in complex systems
  • Many-body Hamiltonians in 1+ dimensions (Hubbard, Anderson, Haldane, etc.)
  • Berry phases, geometric phases, and topological phases in condensed matter systems
  • [non-expertise] Topological Quantum Computing with anyons

© Siddhant Singh, 2020