papers

Publications (39)

quant-ph2024

Variational Quantum Simulation of Anyonic Chains

Ananda Roy

Anyonic chains provide lattice realizations of a rich set of quantum field theories in two space-time dimensions. The latter play a central role in the investigation of generalized…

quant-ph2024

Efficient Quantum Circuits based on the Quantum Natural Gradient

Ananda Roy, Sameer Erramilli, Robert M. Konik

Efficient preparation of arbitrary entangled quantum states is crucial for quantum computation. This is particularly important for noisy intermediate scale quantum simulators relyi…

quant-ph2022

Entanglement entropy in critical quantum spin chains with boundaries and defects

Ananda Roy, Hubert Saleur

Entanglement entropy (EE) in critical quantum spin chains described by 1+1D conformal field theories contains signatures of the universal characteristics of the field theory. Bound…

quant-ph2024

Ising Meson Spectroscopy on a Noisy Digital Quantum Simulator

Christopher Lamb, Yicheng Tang, Robert Davis +1

Quantum simulation has the potential to be an indispensable technique for the investigation of non-perturbative phenomena in strongly-interacting quantum field theories (QFTs). In…

cond-mat.str-el2023

Topological Interfaces of Luttinger Liquids

Ananda Roy, Hubert Saleur

Topological interfaces of two-dimensional conformal field theories contain information about symmetries of the theory and exhibit striking spectral and entanglement characteristics…

quant-ph2023

Quantum Electronic Circuits for Multicritical Ising Models

Ananda Roy

Multicritical Ising models and their perturbations are paradigmatic models of statistical mechanics. In two space-time dimensions, these models provide a fertile testbed for invest…

quant-ph2021

The quantum sine-Gordon model with quantum circuits

Ananda Roy, Dirk Schuricht, Johannes Hauschild +2

Analog quantum simulation has the potential to be an indispensable technique in the investigation of complex quantum systems. In this work, we numerically investigate a one-dimensi…

quant-ph2016

Concurrent Remote Entanglement with Quantum Error Correction

Ananda Roy, A. Douglas Stone, Liang Jiang

Remote entanglement of distant, non-interacting quantum entities is a key primitive for quantum information processing. We present a new protocol to remotely entangle two stationar…

quant-ph2018

Quantum-limited Parametric Amplification with Josephson Circuits in the Regime of Pump Depletion

Ananda Roy, Michel Devoret

Linear parametric amplification is a key operation in information processing. Our interest here is quantum-limited parametric amplification, , amplification of quantum signal…

cond-mat.mes-hall2014

Asymmetric frequency conversion in nonlinear systems driven by a biharmonic pump

Archana Kamal, Ananda Roy, John Clarke +1

A novel mechanism of asymmetric frequency conversion is investigated in nonlinear dispersive devices driven parametrically with a biharmonic pump. When the relative phase between t…

hep-th2026

Lattice Topological Defects in Non-Unitary Conformal Field Theories

Madhav Sinha, Thiago Silva Tavares, Hubert Saleur +1

Topological defects play a fundamental role in the investigation of symmetries in quantum field theories. For conformal field theories in two space-time dimensions, it is possible…

cond-mat.mes-hall2020

Quantum phases of a one-dimensional Majorana-Bose-Hubbard model

Ananda Roy, Johannes Hauschild, Frank Pollmann

Majorana zero modes (MZM-s) occurring at the edges of a 1D, p-wave, spinless superconductor, in absence of fluctuations of the phase of the superconducting order parameter, are qui…

hep-th2022

Entanglement entropy and negativity in the Ising model with defects

David Rogerson, Frank Pollmann, Ananda Roy

Defects in two-dimensional conformal field theories (CFTs) contain signatures of their characteristics. In this work, we compute the entanglement entropy (EE) and the entanglement…

cond-mat.mes-hall2017

Quantum phase transitions of the Majorana toric code in the presence of finite Cooper-pair tunneling

Ananda Roy, Barbara M. Terhal, Fabian Hassler

The toric code based on Majorana fermions on mesoscopic superconducting islands is a promising candidate for quantum information processing. In the limit of vanishing Cooper-pair t…

quant-ph2025

Boundary Conditions for the Entanglement Cut in 2D Conformal Field Theories

Ananda Roy, Sergei L. Lukyanov, Hubert Saleur

The entanglement spectra for a subsystem in a spin chain fine-tuned to a quantum-critical point contains signatures of the underlying quantum field theory that governs its low-ener…

cond-mat.stat-mech2024

Simulating the Transverse Field Ising Model on the Kagome Lattice using a Programmable Quantum Annealer

Pratyankara Narasimhan, Stephan Humeniuk, Ananda Roy +1

The presence of competing interactions due to geometry leads to frustration in quantum spin models. As a consequence, the ground state of such systems often displays a large degene…

hep-th2024

Integrable RG Flows on Topological Defect Lines in 2D Conformal Field Theories

Thiago Silva Tavares, Madhav Sinha, Linnea Grans-Samuelsson +2

Topological defect lines (TDLs) in two-dimensional conformal field theories (CFTs) are standard examples of generalized symmetries in quantum field theory. Integrable lattice incar…

cond-mat.stat-mech2020

Critical properties of the Ising model in hyperbolic space

Nikolas P. Breuckmann, Benedikt Placke, Ananda Roy

The Ising model exhibits qualitatively different properties in hyperbolic space in comparison to its flat space counterpart. Due to the negative curvature, a finite fraction of the…

quant-ph2017

Topological Quantum Computing

Ananda Roy, David P. DiVincenzo

This set of lecture notes forms the basis of a series of lectures delivered at the 48th IFF Spring School 2017 on Topological Matter: Topological Insulators, Skyrmions and Majorana…

hep-th2023

Lattice Realizations of Topological Defects in the critical (1+1)-d Three-State Potts Model

Madhav Sinha, Fei Yan, Linnea Grans-Samuelsson +2

Topological/perfectly-transmissive defects play a fundamental role in the analysis of the symmetries of two dimensional conformal field theories (CFTs). In the present work, spin c…

cond-mat.mes-hall2018

Charge response of the Majorana toric code

Ananda Roy, Fabian Hassler

At zero temperature, a two dimensional lattice of Majorana zero modes on mesoscopic superconducting islands has a topologically ordered toric code phase. Recently, a Landau field t…

quant-ph2024

Quantum Circuit Optimization using Differentiable Programming of Tensor Network States

David Rogerson, Ananda Roy

Efficient quantum circuit optimization schemes are central to quantum simulation of strongly interacting quantum many body systems. Here, we present an optimization algorithm which…

quant-ph2023

Soliton Confinement in a Quantum Circuit

Ananda Roy, Sergei L. Lukyanov

Confinement of topological excitations into particle-like states - typically associated with theories of elementary particles - are known to occur in condensed matter systems, aris…

quant-ph2025

Signatures of Topological Symmetries on a Noisy Quantum Simulator

Christopher Lamb, Robert M. Konik, Hubert Saleur +1

Topological symmetries, invertible and otherwise, play a fundamental role in the investigation of quantum field theories. Despite their ubiquitous importance across a multitude of…

hep-th2022

Entanglement entropy in the Ising model with topological defects

Ananda Roy, Hubert Saleur

Entanglement entropy~(EE) contains signatures of many universal properties of conformal field theories~(CFTs), especially in the presence of boundaries or defects. In particular, {…

cond-mat.mes-hall2018

Dual Shapiro steps of a phase-slip junction in the presence of a parasitic capacitance

Lisa Arndt, Ananda Roy, Fabian Hassler

Bloch oscillations in a single Josephson junction in the phase-slip regime relate current to frequency. They can be measured by applying a periodic drive to a DC-biased, small Jose…

cond-mat.str-el2018

Dynamical structure factor in the non-Abelian phase of the Kitaev honeycomb model in the presence of quenched disorder

Daniel Otten, Ananda Roy, Fabian Hassler

Kitaev's model of spins interacting on a honeycomb lattice describes a quantum spin-liquid, where an emergent static gauge field is coupled to Majorana fermions. In…

cond-mat.stat-mech2020

Entanglement Hamiltonian of the 1+1-dimensional free, compactified boson conformal field theory

Ananda Roy, Frank Pollmann, Hubert Saleur

Entanglement or modular Hamiltonians play a crucial role in the investigation of correlations in quantum field theories. In particular, in 1+1 space-time dimensions, the spectra of…

cond-mat.mes-hall2016

Introduction to Quantum-limited Parametric Amplification of Quantum Signals with Josephson Circuits

Michel Devoret, Ananda Roy

This short and opinionated review starts with a concept of quantum signals at microwave frequencies and focuses on the principle of linear parametric amplification. The amplificati…

quant-ph2015

Remote Entanglement by Coherent Multiplication of Concurrent Quantum Signals

Ananda Roy, Liang Jiang, A. Douglas Stone +1

Concurrent remote entanglement of distant, non-interacting quantum entities is a crucial function for quantum information processing. In contrast with the existing protocols which…

quant-ph2026

Universal Euler-Cartan Circuits for Quantum Field Theories

Ananda Roy, Robert M. Konik, David Rogerson

Quantum computers can efficiently solve problems which are widely believed to lie beyond the reach of classical computers. In the near-term, hybrid quantum-classical algorithms, wh…

hep-th2026

Simulating Lattice Gauge Theories with Virtual Rishons

David Rogerson, João Barata, Robert M. Konik +2

Classical tensor network and hybrid quantum-classical algorithms are promising candidates for the investigation of real-time properties of lattice gauge theories. We develop here a…

hep-th2025

Integrability and lattice discretizations of all Topological Defect Lines in minimal CFTs

Madhav Sinha, Thiago Silva Tavares, Ananda Roy +1

We discuss in this paper the lattice discretizations of all topological defect lines (TDLs) for diagonal, minimal CFTs, using integrable restricted solid-on-solid (RSOS) models. Fo…

cond-mat.mes-hall2019

Quantum Electronic Circuit Simulation of Generalized sine-Gordon Models

Ananda Roy, Hubert Saleur

Investigation of strongly interacting, nonlinear quantum field theories (QFT-s) remains one of the outstanding challenges of modern physics. Here, we describe analog quantum simula…

physics.optics2013

Three-wave mixing with three incoming waves: Signal-Idler Coherent Cancellation and Gain Enhancement in a Parametric Amplifier

Flavius Schackert, Ananda Roy, Michael Hatridge +2

Coherent, purely-dispersive three-wave mixing systems in optics and superconducting microwave circuits can be operated as parametric amplifiers, generating from a pump wave at one…

quant-ph2014

Continuous Generation and Stabilization of Mesoscopic Field Superposition States in a Quantum Circuit

Ananda Roy, Zaki Leghtas, A. Douglas Stone +2

While dissipation is widely considered as being harmful for quantum coherence, it can, when properly engineered, lead to the stabilization of non-trivial pure quantum states. We pr…

cond-mat.mes-hall2019

Topological ordering in the Majorana Toric Code

Alexander Ziesen, Fabian Hassler, Ananda Roy

At zero temperature, a two-dimensional lattice of Majorana zero modes on mesoscopic superconducting islands exhibits a topologically-ordered toric code phase. Recently, a Landau fi…

hep-ph2010

Resonant production of the sterile neutrino dark matter and fine-tunings in the [nu]MSM

Ananda Roy, Mikhail Shaposhnikov

The generation of lepton asymmetry below the electroweak scale has a considerable impact on production of dark matter sterile neutrinos. Oscillations or decays of the heavier steri…

hep-ph2010

Renormalization of masses of sterile neutrinos in the [nu]MSM

Ananda Roy

The quasi-degeneracy of heavier sterile neutrino masses in the Neutrino Minimal Standard Model (MSM) facilitates the production of lepton asymmetry below the electroweak scale.…