Postselection as a Resource for Quantum Control: Dynamics, Geometry, and Topology in Open Systems

Date

Feb 23, 2026

Time

4:30 PM - 5:30 PM

Speaker

Prof Kater Murch

Affiliation

UC Berkeley

Series

MPI-PKS Kolloquium

Language

en

Main Topic

Physik

Other Topics

Physik

Description

Postselection—the conditioning of quantum dynamics on specific measurement outcomes—is a powerful but subtle control resource in open quantum systems. By selecting particular measurement trajectories, postselection fundamentally reshapes quantum evolution, leading to dynamics that cannot be described by standard unitary or Lindbladian frameworks alone. In this colloquium, I will introduce how postselection gives rise to effective non-Hermitian dynamics, alters measurement backaction, and enables access to new geometric and topological phenomena. Using superconducting quantum circuits with engineered dissipation as a concrete experimental platform, I will illustrate how postselecting on “no-jump” trajectories generates non-Hermitian Hamiltonians with exceptional points, complex energy landscapes, and unconventional adiabatic behavior. I will show how these features manifest in phenomena such as weak-values, complex Berry phases, topological state transfer, and nonlinear quantum evolution. Beyond specific experiments, postselection provides a bridge between measurement theory, non-Hermitian physics, and quantum control. From this perspective, postselection emerges as a versatile control resource that bridges measurement theory, non-Hermitian physics, and dissipative quantum control, touching on Liouvillian dynamics, quantum trajectories, and stabilization of open-system evolution.

Last modified: Feb 4, 2026, 7:37:11 AM