Coronavirus (Covid-19): Latest updates and information
Skip to main content Skip to navigation

Leonardo Benini

I am a fourth-year PhD student in Theoretical Physics at Warwick. I am part of the Disordered Quantum Systems (DisQS) group, headed by prof. Rudolf Römer.

Research Interests

My main research interests lie around theoretical aspects of condensed matter and many-body physics, with particular focus on topics such as localization and thermalization in closed quantum systems, entanglement properties, non-equilibrium dynamics and transport in quantum devices.


Research

  • Localisation and spin-filtering effects
    • Study of spin filtering effects in disordered one-dimensional atomic chains. We investigated a simple tight-binding Hamiltonian to understand the stability of spin-polarised transport of states with an arbitrary spin content in the presence of disorder-induced localisation. Depending on the value of spin, the chain of magnetic atoms unravels a hidden transverse dimensionality that can be exploited to engineer energy regimes where only a selected spin state is allowed to retain large localisation lengths. Our results show that the spin filtering effect is robust against weak disorder and hence the proposed model should be a good candidate for experimental realisations of spin-selective transport devices.
  • Dynamical probes of dephasing in disordered many-body systems
    • In the context of Many-Body Localisation (MBL), we recently showed that strongly localized l-bits bear a dramatic universal signature, accessible to state-of-the-art quantum simulators, in the form of periodic cusp singularities in the Loschmidt echo following a quantum quench from a Néel/charge-density-wave state. We built a simple analytical model of Rabi oscillations of an ensemble of independent two-level systems, which capures this singular behavior, as well as the short-time dynamics of other observables (entanglement entropy and imbalance). In the case of interacting localized phases, the dynamics at longer times shows a sharp crossover to a faster decay of the Loschmidt echo singularities, offering an experimentally accessible signature of the interactions between l-bits.
  • Interferometric study of MBL systems spectra
    • We are studying statistical properties of energy spectra of many-body hamiltonians in the presence of strong disorder. We built an interferometric protocol based on the preparation of copies of disordered many-body systems, whose effective realisation is affected by a systematic noise. Through the calculation of the overlap between the states of the two systems during time evolution, it is possible to access spectral properties of the system, revealing intriguing insights into the sensitivity of MBL systems to noise and small perturbations.

Education

  • MSc in Condensed Matter Physics - Alma Mater Studiorum, University of Bologna (2014-2017)
  • BSc in Physics - Alma Mater Studiorum, University of Bologna (2011-2014)

Teaching

2018-2019: Demonstrator 3rd year Physics Lab course.

2017-2018: Demonstrator 3rd year Physics Lab course.


Publications

"Loschmidt echo singularities as dynamical signatures of strongly localized phases", arXiv:2008.12719 (2020)

"Spin-polarized localization in a magnetized chain", Scientific Reports 9, 5930 (2019)

Photo

L dot Benini at warwick dot ac dot uk