6 papers
Valley population of donor states in highly strained silicon
B. Voisin, K. S. H. Ng, J. Salfi +13
Strain is extensively used to controllably tailor the electronic properties of materials. In the context of indirect band-gap semiconductors such as silicon, strain lifts the valle…
Pattern Formation in Quantum Ferrofluids: from Supersolids to Superglasses
J. Hertkorn, J. -N. Schmidt, M. Guo +7
Pattern formation is a ubiquitous phenomenon observed in nonlinear and out-of-equilibrium systems. In equilibrium, quantum ferrofluids formed from ultracold atoms were recently sho…
Supersolidity in Two-Dimensional Trapped Dipolar Droplet Arrays
J. Hertkorn, J. -N. Schmidt, M. Guo +8
We theoretically investigate the ground states and the spectrum of elementary excitations across the superfluid to droplet crystallization transition of an oblate dipolar Bose-Eins…
Roton Excitations in an Oblate Dipolar Quantum Gas
Jan-Niklas Schmidt, Jens Hertkorn, Mingyang Guo +7
We observe signatures of radial and angular roton excitations around a droplet crystallization transition in dipolar Bose-Einstein condensates. In situ measurements are used to cha…
Density Fluctuations across the Superfluid-Supersolid Phase Transition in a Dipolar Quantum Gas
J. Hertkorn, J. -N. Schmidt, F. Böttcher +8
Phase transitions share the universal feature of enhanced fluctuations near the transition point. Here we show that density fluctuations reveal how a Bose-Einstein condensate of di…
New states of matter with fine-tuned interactions: quantum droplets and dipolar supersolids
Fabian Böttcher, Jan-Niklas Schmidt, Jens Hertkorn +5
Quantum fluctuations can stabilize Bose-Einstein condensates (BEC) against the mean-field collapse. Stabilization of the condensate has been observed in quantum degenerate Bose-Bos…