Speaker: Sam Dai (Northeastern University)
Title:  Locality Requirements for Quantum Error-Correcting Codes

Date: Tuesday, December 3, 2024
Time: 11 am-12 pm
Location: EXP-610

Abstract: Quantum error-correcting codes provide a promising avenue towards fault-tolerant quantum computation. Unfortunately, the practical constraint of spatial locality places stringent limitations on their parameters. For example, a seminal result of Bravyi-Poulin-Terhal (BPT) says that a $[[n,k,d]]$ quantum code with 2D-locality must satisfy $kd^2 \leq O(n)$.

Going beyond the BPT bound, a natural question asks how much "non-locality" is needed if we want better code parameters? In particular: 

(i) How long must non-local interactions be?
(ii) How many long-range interactions are required? 

In this talk, I will provide a complete answer to these questions by giving asymptotically optimal lower bounds on both the interaction count and interaction length as a function of the code parameters. Based on joint work with Ray Li (arXiv:2409.15203).

Biography:   Samuel Dai is a PhD student in the Physics department at Northeastern University. He is broadly interested in developing provable methods for encoding, decoding, and operating on quantum data for fault-tolerant quantum computation.