Seminar

Zlatko Minev is the technical lead and manager of the following groups at IBM Quantum - Qiskit Leap (quantum computing research) and Qiskit Metal (quantum hardware). His background is in experimental and theoretical quantum computing, software, fundamental and applied physics. Meet him for an informal chat about Quantum-related industry opportunities and his career progression.

A quantum speedup occurs when a computational problem can be solved faster on a quantum computer than on a classical computer. This thesis studies the circumstances under which quantum speedups can arise from three perspectives. First, we study the structure of the problem. We show how a problem’s symmetries relate to whether it can admit a polynomial or superpolynomial quantum speedup. In particular, we show that the computation of any partial function of a hypergraph’s adjacency matrix can only admit a polynomial speedup.

Quantum Many-Body scars represent a new paradigm of breaking eigenstate thermalization hypothesis—a vanishing number of states in the spectrum exhibit area law entanglement while being dispersed at equally spaced energies throughout a spectrum of volume-law entangled states. This is in stark contrast to many-body localization, where all eigenstates are area-law entangled, or a thermalizing system, where states are volume law entangled. Despite the fact that very few states exhibit such low entanglement, they have a remarkable effect on the dynamics of the system.

In recent years, there have been rapid breakthroughs in quantum technologies that offer new opportunities for advancing the understanding of basic quantum phenomena; realizing novel strongly correlated systems; and enhancing applications in quantum communication, computation, and sensing. Cutting edge quantum technologies simultaneously require high fidelity quantum-limited measurements and control.

Majority vote is a basic method for amplifying correct outcomes that is widely used in computer science and beyond. While it can amplify the correctness of a quantum device with classical output, the analogous procedure for quantum output is not known. We introduce quantum majority vote as the following task: given a product state ∣ψ_1〉⊗⋯⊗∣ψ_n〉 where each qubit ∣ψ_i〉 is in one of two orthogonal states ∣ψ〉 or ∣ψ^⊥〉, output the majority state. We show that an optimal algorithm for this problem achieves worst-case fidelity of 1/2 + Θ(1/n).

Despite growing interest in beyond-group symmetries in quantum condensed matter systems, there are relatively few microscopic lattice models explicitly realizing these symmetries, and many phenomena have yet to be generalized at the microscopic level. In this work, we show that the generalized cluster state introduced in arXiv:1408.6237 is an SPT protected by categorical symmetry.

In this talk I will give a brief introduction about the security of various symmetric-key constructions against quantum attackers in two models: Q1 model and Q2 model. I’ll talk about the difference between those two models, why Q1 model is more realistic and some recent results about the post-quantum security of block ciphers in the Q1 model.

Reference: G. Alagic, C. Bai, J. Katz, C. Majenz, Post-Quantum Security of the Even-Mansour Cipher https://eprint.iacr.org/2021/1601.
 

Quantum Spin Liquids are exotic phases of matter whose low-energy physics is described as the deconfined phase of an emergent gauge theory. With recent theory proposals and an experiment showing preliminary signs of Z2 topological order, arrays of neutral atoms with Rydberg interactions have emerged as a promising platform to realize a spin liquid. In this work, we propose a way to realize the deconfined phase of U(1) gauge theory in 3 spatial dimensions from Rydberg interactions on a pyrochlore lattice.

In this talk, I will give a brief introduction to nonlocal games, followed by a discussion on the results from [1]. In this paper Kalai et al. show a connection between nonlocal games and classical verification of quantum advantage. Specifically, they construct a framework for compiling a k-prover nonlocal game into a single-prover interactive game.

How to write successful grant proposals, pushing your writing skills to the next level. Mohammad will provide a general overview of grant writing and focus on proposals for research, a key mandate of the NSF grant for the Quantum Leap Challenge Institute for Robust Quantum Simulation.

Please prepare your questions in advance and send them to rqs-seed@umiacs.umd.edu.