86 citations · 422 across the 14 of their papers we have counts for
14 papers
Duel-Evolve: Reward-Free Test-Time Scaling via LLM Self-Preferences
Sweta Karlekar, Carolina Zheng, Magnus Saebo +5
Many applications seek to optimize LLM outputs at test time by iteratively proposing, scoring, and refining candidates over a discrete output space. Existing methods use a calibrat…
Evidence for the Alternating Next-Nearest Neighbor model in the dynamic behavior of a frustrated antiferromagnet
Adra Carr, John Bowlan, 3 +12
X-ray photon correlation spectroscopy (XPCS) enables us to study dynamics of antiferromagnets. Using coherent soft X-ray diffraction, we resonantly probe Mn and Co Bragg peaks in t…
Manipulating Multiple Order Parameters via Oxygen Vacancies: The case of Eu0.5Ba0.5TiO3-δ
Weiwei Li, Qian He, Le Wang +27
Controlling functionalities, such as magnetism or ferroelectricity, by means of oxygen vacancies (VO) is a key issue for the future development of transition metal oxides. Progress…
Probing and controlling terahertz-driven structural dynamics with surface sensitivity
P. Bowlan, J. Bowlan, S. A. Trugman +8
Intense, single-cycle terahertz (THz) pulses offer a promising approach for understanding and controlling the properties of a material on an ultrafast time scale. In particular, re…
Effects of biaxial strain on the improper multiferroicity in h-LuFeO3 films
Kishan Sinha, Yubo Zhang, Xuanyuan Jiang +11
Elastic strain is potentially an important approach in tuning the properties of the improperly multiferroic hexagonal ferrites, the details of which have however been elusive due t…
Magnetism and exchange interaction of small rare-earth clusters; Tb as a representative
Lars Peters, Saurabh Ghosh, Biplab Sanyal +9
Here we follow, both experimentally and theoretically, the development of magnetism in Tb clusters from the atomic limit, adding one atom at a time. The exchange interaction is, su…
Ultrafast spin density wave transition in Chromium governed by thermalized electron gas
C. W. Nicholson, C. Monney, R. Carley +4
The energy and momentum selectivity of time- and angle-resolved photoemission spectroscopy is exploited to address the ultrafast dynamics of the antiferromagnetic spin density wave…
Probing ultrafast spin dynamics in the antiferromagnetic multiferroic HoMnO through a magnon resonance
P. Bowlan, S. A. Trugman, J. Bowlan +5
We demonstrate a new approach for directly measuring the ultrafast energy transfer between elec- trons and magnons, enabling us to track spin dynamics in an antiferromagnet (AFM).…
Ultrafast Carrier Dynamics in the Large Magnetoresistance Material WTe
Y. M. Dai, J. Bowlan, H. Li +10
Ultrafast optical pump-probe spectroscopy is used to track carrier dynamics in the large magnetoresistance material WTe. Our experiments reveal a fast relaxation process occu…
Time-resolved terahertz dynamics in thin films of the topological insulator BiSe
R. Valdés Aguilar, J. Qi, M. Brahlek +7
We use optical pump--THz probe spectroscopy at low temperatures to study the hot carrier response in thin BiSe films of several thicknesses, allowing us to separate the bul…
Structure of Magnetic Lanthanide Clusters from Far-IR Spectroscopy: Tb (n = 5-9)
John Bowlan, Dan J. Harding, Jeroen Jalink +3
Small lanthanide clusters have interesting magnetic properties, but their structures are unknown. We have identified the structures of small terbium cluster cations Tb (n = 5-9) in…
Bistability of Free Cobalt and Iron Clusters
Xiaoshan Xu, Shuangye Yin, Ramiro Moro +3
The cobalt and iron clusters CoN, FeN (20 < N < 150) measured in a cryogenic molecular beam are found to be bistable with magnetic moments per atom both μN/N 2μB in the ground stat…
How Metallic are Small Sodium Clusters?
John Bowlan, Anthony Liang, Walt A. de Heer
Cryogenic cluster beam experiments have provided crucial insights into the evolution of the metallic state from the atom to the bulk. Surprisingly, one of the most fundamental meta…
Non-classical dipoles in cold niobium clusters
Xiaoshan Xu, Shuangye Yin, Ramiro Moro +3
Electric deflections of niobium clusters in molecular beams show that they have permanent electric dipole moments at cryogenic temperatures but not higher temperatures, indicating…