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Search Publications by: Ian Spielman (Fed)

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Displaying 26 - 50 of 206

Floquet engineering topological Dirac bands

July 22, 2022
Author(s)
Ian Spielman, Mingwu Lu, Amilson R. Fritsch, Graham Reid, Alina Pineiro Escalera
We experimentally realized a time-periodically modulated 1D lattice for ultracold atoms featuring a pair of linear bands, each associated with a Floquet winding number: a topological invariant. These bands are spin-momentum locked and almost perfectly

Accurate Determination of Hubble Attenuation and Amplification in Expanding and Contracting Cold-Atom Universes

February 28, 2022
Author(s)
Swarnav Banik, Monica Gutierrez Galan, Hector Sosa Martinez, 1, Madison Anderson, Stephen Eckel, Ian Spielman, Gretchen K. Campbell
In the expanding universe, relativistic scalar fields are thought to be attenuated by "Hubble friction," which results from the dilation of the underlying spacetime metric. By contrast, in a contracting universe this pseudofriction would lead to

Wilson loop and Wilczek-Zee phase from a non-Abelian gauge field

September 30, 2021
Author(s)
Ian Spielman, Francisco Salces Carcoba, Andika Putra, Yuchen Yue, Seiji Sugawa
Quantum states can acquire a geometric phase called the Berry phase after adiabatically traversing a closed loop, which depends on the path not the rate of motion. The Berry phase is analogous to the Aharonov–Bohm phase derived from the electromagnetic

Machine-learning enhanced dark soliton detection in Bose-Einstein condensates

June 15, 2021
Author(s)
Shangjie Guo, Amilson R. Fritsch, Ian Spielman, Justyna Zwolak
Most data in cold-atom experiments comes from images, the analysis of which is limited by our preconceptions of the patterns that could be present in the data. We focus on the well-defined case of detecting dark solitons—appearing as local density

Coherence and decoherence in the Harper-Hofstadter model

May 19, 2021
Author(s)
Ian Spielman, Qiyu Liang, Dimi Trypogeorgos, Ana Valdes-Curiel, Junheng Tao, Mingshu Zhao
We quantum simulated the 2D Harper-Hofstadter (HH) lattice model in a highly elongated tube geometry—three sites in circumference—using an atomic Bose-Einstein condensate. In addition to the usual transverse (out-of-plane) magnetic flux, piercing the

Multiple-camera defocus imaging of ultracold atomic gases

May 13, 2021
Author(s)
Ian Spielman, Francisco Salces Carcoba, Yuchen Yue, Seiji Sugawa, Abigail Perry
In cold atom experiments, each image of light refracted and absorbed by an atomic ensemble carries a remarkable amount of information. Numerous imaging techniques including absorption, fluorescence, and phase-contrast are commonly used. Other techniques

Feedback Induced Magnetic Phases in Binary Bose-Einstein Condensates

December 7, 2020
Author(s)
Ian B. Spielman, Shangjie Guo, Hilary M. Hurst
Weak measurement in tandem with real-time feedback control is a new route toward engineering novel non-equilibrium quantum matter. Here we develop a theoretical toolbox for quantum feedback control of multicomponent Bose-Einstein condensates (BECs) using

Enhanced transport of spin-orbit coupled Bose gases in disordered potentials

September 17, 2020
Author(s)
Yuchen Yue, Ian Spielman, Carlos S? de Melo
Anderson localization is single particle localization phenomena in disordered media that is accompanied by an absence of diffusion. Spin-orbit coupling (SOC) describes an interaction between a particle's spin and its momentum that directly affects its

Creating solitonic excitations with controllable velocity in Bose-Einstein condensates

May 20, 2020
Author(s)
Amilson R. Fritsch, Mingwu Lu, Alina M. Pineiro Escalera, Graham H. Reid, Ian Spielman
Established techniques for deterministically creating dark solitons in repulsively interacting atomic Bose-Einstein condensates (BECs) can only access a narrow range of soliton velocities. Because velocity a ects the stability of individual solitons and

Realization of a deeply subwavelength adiabatic optical lattice

February 12, 2020
Author(s)
Ian B. Spielman, Ana Valdes Curiel, Russell P. Anderson, T. Andrijauskas, Gediminas Juzeliunas, Qiyu Liang, Junheng Tau, Dimitrius Trypogeorgos, Mingshu Zhao
We propose and realize a deeply sub-wavelength optical lattice for ultracold neutral atoms using $N$ resonantly Raman-coupled internal degrees of freedom. Although counter-propagating lasers with wavelength $\lambda$ provided two-photon Raman coupling, the

Repeated Measurements with Minimally Destructive Partial-Transfer Absorption Imaging

December 2, 2019
Author(s)
Ian B. Spielman, Ana Valdes Curiel, Dimitris Trypogeorgos, Erin Marshall, Nathan Lundblad
We demonstrate partial-transfer absorption imaging as a technique for repeatedly imaging an ultracold atomic ensemble with minimal perturbation. We prepare an atomic cloud in a state that is dark to the imaging light and then use a microwave pulse to