ITAMP News

It's always great news that one of our own is nominated for a major prize: in this case, Annabelle Bohrdt is a finalist for the 2022 APS Debbie Jin Prize. She will give an invited talk at the special DAMOP Thesis Prize session in Orlando, FL. We're ecstatic.

She has also won the Friedrich Hirzebruch Doctoral Prize 2022 for her dissertation "Probing strongly correlated many-body systems with quantum simulation". The prize announcement is here: https://www.studienstiftung.de/auszeichnungen/promotionspreise/preistrae....

https://quantumfrontiers.com/2021/11/21/i-wish-you-a-charles-river/

https://news.harvard.edu/gazette/story/2021/07/harvard-led-physicists-cr...

Youtube: https://youtu.be/VcS_FznLURM

Guest Speaker: Professor Maxim Olshanii
Affiliation: University of Massachusetts Boston
Date: May 20, 2021
Time: 1:00 PM Eastern time

Triangular Gross-Pitaevskii breathers and Damski-Chandrasekhar shock waves

The recently proposed map [arXiv:2011.01415] between the hydrodynamic equations governing the two-dimensional triangular cold-bosonic breathers [Phys. Rev. X 9, 021035 (2019)] and the high-density zero-temperature triangular free-fermionic clouds, both trapped harmonically, perfectly explains the former phenomenon but leaves uninterpreted the nature of the initial (t=0) singularity. This singularity is a density discontinuity that leads, in the bosonic case, to an infinite force at the cloud edge. The map itself becomes invalid at time t=T/4. Here, we first map -- using the scale invariance of the problem -- the trapped motion to an untrapped one. Then we show that in the new representation, the solution [arXiv:2011.01415] becomes, along a ray in the direction normal to one of the three edges of the initial cloud, a freely propagating one-dimensional shock wave of a class proposed by Damski in [Phys. Rev. A 69, 043610 (2004)]. There, for a broad class of initial conditions, the one-dimensional hydrodynamic equations can be mapped to the inviscid Burgers' equation, a nonlinear transport equation. More specifically, under the Damski map, the t=0 singularity of the original problem becomes, verbatim, the initial condition for the wave catastrophe solution found by Chandrasekhar in 1943 [Ballistic Research Laboratory Report No. 423 (1943)]. At t=T/8, our interpretation ceases to exist: at this instance, all three effectively one-dimensional shock waves emanating from each of the three sides of the initial triangle collide at the origin, and the 2D-1D correspondence between the solution of [arXiv:2011.01415] and the Damski-Chandrasekhar shock wave becomes invalid.

Rydberg systems: from the exotic to applications

Rydberg atoms has emerged as a versatile platform for different applications in quantum technology from computing and simulation to sensing and imaging [1]. In this talk, I will briefly mention the different Rydberg projects in Durham, and then focus on our recent work on Rydberg quantum optics. In this experiment, we store optical photons in a cold atomic ensemble in the form of Rydberg polaritons. In recent work, we have looked at the potential of Rydberg polaritons in the context of quantum information. We show that Rydberg polaritons have a number of attractive features: The large dipole moments between Rydberg states enables fast single-qubit rotations that are independent of atoms number. The combined atomic and photonic character of the polariton [2] allows fast photonic read-out of the quantum state. Finally, as the quantum information is shared amongst many atoms, there is an in-built robustness to atom loss [3]. Experiments on the extension to higher dimensions, photonic qutrits, will be presented.

References

[1] CS Adams et al, Rydberg atom quantum technologies, J Phys B 53, 012002 (2019).
[2] Y Jiao et al, Single-photon stored-light interferometry, Opt Lett 45, 5888 (2020).
[3]NLR Spong et al, The Robustness of a Collectively Encoded Rydberg Qubit, arXiv:2010.11794 (2020).