Spring 2022

Abstract: Semiconductor moiré materials provide a physical realization of the Kane-Mele-Hubbard model for studies of the combined effects of non-trivial band topology and strong electronic correlations. In this talk, I will discuss the rich electronic phase diagram of the Kane-Mele-Hubbard model realized in AB-stacked MoTe2/WSe2 moiré bilayers.

Learning how to create, study, and manipulate highly entangled states of matter is key to understanding exotic phenomena in condensed matter and high energy physics, as well as to the development of useful quantum computers. In this talk, I will discuss recent experiments where we demonstrated the realization of a quantum spin liquid phase using Rydberg atoms on frustrated lattices and a new architecture based on the coherent transport of entangled atoms through a 2D array.

In the past decade a new technology domain of quantum sound has emerged. Unlike electrical and optical systems, which are governed by fundamental equations of electromagnetism, acoustical and vibrational phenomena are described by the equations of elastic waves in solid bodies. They are subject to different limitations and can reach different regimes of behavior. Sound is different.

Dissertation Committee Chair: Prof. Vladimir Manucharyan
Committee: 
Prof. Steven Anlage
Prof. Victor Galitski
Prof. Alicia Kollar
Prof. Ichiro Takeuchi

The field of Quantum Information is of great excitement in both fundamental physics and industry. One promising platform for quantum computing is gate-defined quantum dots in semiconductors. The greatest limiting factor currently is that delicate quantum states can lose their quantum nature due to interactions with their environment. Other open challenges are to coherently control large-scale spin qubits and develop methods to entangle quantum bits that are separated by significant distances.

Abstract: In most common metals, the many-body physics of their electrons can be described in terms of additive, weakly interacting excitations called quasiparticles. However, several examples of metallic states of matter related to the “high” temperature superconductors and other strongly correlated materials exist, in which strong electron-electron interactions near putative quantum critical points or phases lead to very unconventional physics that cannot be described by quasiparticles, even as the electron liquid remains compressible.

Abstract: Quantum computers hold the promise of solving computational problems which are intractable using conventional methods. For fault-tolerant operation quantum computers must correct errors occurring due to unavoidable decoherence and limited control accuracy. Here, we demonstrate quantum error correction using the surface code, which is known for its exceptionally high tolerance to errors. Using 17 physical qubits in a superconducting circuit we encode quantum information in a distance-three logical qubit building up on recent distance-two error detection experiments [1].

Abstract: In the past decade, quantum simulators have increased in their power and scope, offering exquisite dynamical control of tens or even hundreds of individual atoms. Concurrently, a topological revolution in our understanding of electronic band structures has taken place, driven by the discovery of topological insulators, graphene and other topological materials. Remarkably, these advances can be connected --- the dynamics of driven few level systems can be described using band structures in "synthetic dimensions," one per driving tone.

Abstract: Over the last several decades, entanglement has emerged as a unifying lens for understanding phenomena across many areas in quantum physics. At low energy, the structure of ground state entanglement reflects universal features of the phase of matter. At high energy, the growth of entanglement underlies thermalization and the emergence of statistical mechanics. In this talk, I will describe two recent exact results characterizing entanglement in many-body systems.

Dissertation Committee Chair: Professor Vladimir Manucharyan
Committee:
Professor Alicia Kollar
Professor Maissam Barkeshli
Professor Victor Yakovenko
Professor Andrew Childs (Dean’s Representative)