Upcoming seminars

Projectiles, rockets and quantum backflow

Seminar date and time: 
2022-05-19 16:00
Author: 
Miguel Navascués
Affiliation: 
IQOQI Vienna

Consider a scenario where a non-relativistic one-dimensional quantum particle is prepared in some bounded region of space and left to propagate freely. After a certain amount time, we measure if the particle is in some distant target region. In this talk, I will prove the existence of `ultra-fast' initial quantum states, for which the probability of arrival is greater than that of any classical system prepared in the same region with the same momentum distribution.

Location: 
Contact: 
john

Quantum technologies from a business(?) perspective

Seminar date and time: 
2022-05-12 16:00
Author: 
Victor Gaspar
Affiliation: 
GMV innovations

Many companies are trying to bring to the market the amazing research done by quantum scientists. But making a profitable business from quantum science is a nasty business. In this talk I will try to explain the barriers the companies are facing when exploring a new opportunity based on a novel technology or science concept, the real cost of R&D for a company, and some examples of quantum technology research projects GMV is working on. 

Location: 
Contact: 
john

Testing identity of collections of quantum states: sample complexity analysis

Seminar date and time: 
2022-05-05 16:00
Author: 
Marco Fanizza
Affiliation: 
GIQ, UAB

Abstract: We study the problem of testing identity of a collection of unknown quantum states given sample access to this collection, each state appearing with some known probability. We show that for a collection of d-dimensional quantum states of cardinality N, the sample complexity is O(\sqrt{N}d/\epsilon^2), which is optimal up to a constant. The test is obtained by estimating the mean squared Hilbert-Schmidt distance between the states, thanks to a suitable generalization of the estimator of the Hilbert-Schmidt distance between two unknown states by Bădescu, O'Donnell, and Wright.

Location: 
Contact: 
john

A quantum algorithm for gravitational wave matched filtering

Seminar date and time: 
2022-04-21 16:00
Author: 
Sarah Croke
Affiliation: 
University of Glasgow

 Matched filtering is a signal processing technique used to maximize the signal-to-noise ratio by correlating signal templates with detector data. It is central for detecting the extraordinarily weak signals in the field of gravitational wave astronomy. In cases where the signal is too weak and the template bank is too extensive, the matched filtering process can become computationally unfeasible. Quantum computational devices, currently under development, offer the potential to speed up some computational tasks, compared to what is possible classically.

Contact: 
john

Robustness of non-locality in many-body open quantum systems

Seminar date and time: 
2022-03-31 16:00
Author: 
Carlo Marconi
Affiliation: 
GIQ

Non-locality refers to the existence of correlations between local measurements on a shared resource, that cannot be explained by any local realistic theory. So far, it has been investigated mostly in isolated quantum systems. Here I will show that non-local correlations are present, can be detected and might be robust against noise also in many-body open quantum systems, both in the steady-state or in the transient regime.

Filter functions in quantum phase space representations.

Seminar date and time: 
2022-03-03 16:00
Author: 
Mani Zartab
Affiliation: 
GIQ

Continuous-variable (CV) representation of quantum mechanics plays a major role in quantum information theory and quantum optics, espe- cially in quantum state and process tomography. As an example, one might consider inferring the non-classicality of an unknown state, based on whether or not it can be written as a statistical mixture of classical (coher- ent) states. However, there is a major challenge here: the weight function (P-function) is a highly singular function for most cases. Here is where the concept of filtering is useful.

Location: 
GIQ & Zoom

Kronecker states in quantum information theory

Seminar date and time: 
2022-02-24 16:00
Author: 
Walther González
Affiliation: 
Universidad de los Andes

We call Kronecker states to the ones who belong to the symmetric subspace of the tensor product of three or more irreducible representations of the symmetric group. They are maximally entangled states, allowing us to consider their applications in many protocols of quantum information. In this talk I will describe a procedure that allows us to compute Kronecker states in three parts and recursively obtain Kronecker states with N parts.

Pages

Campus d'excel·lència internacional U A B