Hi all,

There were some last minute scheduling complications, but in the end today's meeting will take place at the usual time and place: at 3:30 pm in room HIT E41.1. Today we'll hear from Andreas Bärtschi of Los Alamos, on "Preparation and Compression of Symmetric Pure Quantum States". For more details, see the abstract below.

Best,

-joe

Preparation and Compression of Symmetric Pure Quantum States ================================================== In this talk I will present a deterministic scheme for the preparation of symmetric pure n-qubit quantum states (symmetric under permutation of the qubits). Implemented as a circuit, our scheme has linear depth, needs no ancilla qubits and -- used in reverse -- yields a quasilinear-depth circuit for efficient compression of symmetric pure states into logarithmically many qubits. The scheme relies on an inductive approach to prepare Dicke states |Dnk⟩, which form an orthonormal basis of the subspace of symmetric pure n-qubit states. We prepare these states, which are equal superpositions of all n-qubit states with Hamming Weight k, using O(nk) gates in O(n) depth. All properties also hold for Linear Nearest Neighbor architectures. Talk based on joint work with Stephan Eidenbenz, "Deterministic Preparation of Dicke States", FCT 2019, arXiv:1904.07358.