I have a varied set of research interests within what I broadly call Quantum Matter. These include strongly correlated materials, impurity models, topological phases of matter and quantum information. However, the main focus of my research has been on open quantum systems driven away from thermal equilibrium by the contact with environments (baths) at different thermodynamic potentials (chemical potential or temperature) which yield thermodynamic flows of particles and/or energy.
My publications are available on:
More information about my research topics is given below.
Non Equilibrium Quantum Matter
Non-equilibrium Quantum Criticality
Quenches and work distributions
Universal signatures of dynamics of quantum systems
Non-equilibrium transport though Magnetic Impurities
Transport & Localization
Non-equilibrium Steady-States
QUANTUM MATERIALS
Topological Phases of Matter
Disorder driven multifractality transition in Weyl nodal loops.
Dirac points merging and wandering in a model Chern insulator.
Entanglement entropy and entanglement spectrum of triplet topological superconductors
Hybrid quantum-classical models
There are systems made of different degrees of freedom that have radically different time scales. Sometimes, one set of these variables can be modeled as having a classical character. This greatly simplifies the analysis and allows to effective study quantum phases with numerically exact methods.
Classical and quantum liquids induced by quantum fluctuations. (2010)
Temperature-driven gapless topological insulator. (2019)
Interaction-tuned Anderson versus Mott localization. (2016)
Impurity models
An impurity (also called zero-dimensional system) is a generic designation of system with a few degrees of freedom in contact with a bath. Despite their apparent simplicity the physics of these systems is rich when strong correlation are included giving rise to the Kondo effect, several kinds of phase transitions, etc...
Superconductivity
Superconductors remain one of the most fascinating materials with important technological applications. Although a great deal is known on how superconductivity works in some compounds, new materials with novel properties and some of the old ones are a source interesting puzzles.
Impact of Atomic-Scale Contact Geometry on Andreev Reflection (2017)
Dissipation in a Simple Model of a Topological Josephson Junction (2014)
Interplay of classical and quantum capacitance in a one dimensional array of Josephson junctions (2014)
Theoretical Description of the Superconducting State of Nanostructures at Intermediate Temperatures: A Combined Treatment of Collective Modes and Fluctuations (2012)
Experimental observation of thermal fluctuations in single superconducting Pb nanoparticles through tunneling measurements (2011)
Strongly-Interacting Electronic Phases
Some electronic system where the electron-electron interactions are large behave quite differently that normal metals or insulators. Their collective excitations can be rather exotic. Quantum spin liquid are one of these examples, there are an unusual phase of matter. Quantum spin liquids are characterized by long-range quantum entanglement, fractionalized excitations, and absence of magnetic order.
QUANTUM INFORMATION
Quantum information refers loosely to a set of processes (algorithms) and setups (devices) used to process information with systems obeying the laws of quantum mechanics. The ultimate goal of quantum information is to be able to build and operate an quantum computer that will outperform the existing ones that are based on classical principles. The search for better devices and algorithms poses some practical and theoretical physical challenges.
Adiabatic Quantum Computation
Adiabatic quantum computing is a model of computation that uses quantum dynamics under adiabatic conditions to perform universal quantum computation. The core idea consist of finding the ground-state of a classical optimization problem using adiabatic quantum evolution that makes use of tunneling. This is a very physical idea that can be tested in simplified models that highlight the relations with quantum phase transitions.
Adiabatic computation : A toy model.
Dynamical properties across a quantum phase transition in the Lipkin-Meshkov-Glick model.
Entanglement Classification
Entanglement is a unique feature of quantum systems at the heart of their contra-intuitive nature. Entangled degrees of freedom cannot be described independently of the state of the others. Systems can be entangled in many different ways. Classifying and describing these forms of entanglement will allow us to better understand the quantum world.
Entanglement and Hilbert space geometry for systems with a few qubits
Entanglement in the Symmetric Sector of n Qubits
Quantum Walks
Quantum walks are the quantum counterpart of classical random walks. They have been used in the design of algorithms of several quantum algorithms. Generalized quantum walk protocols with biased quantum coins arranged in periodic and aperiodic sequences may yield ballistic, sub-ballistic and diffusive spreading.
Aperiodic Quantum Random Walks.