Area of research
Condensed Matter Physics · Radiation
Research interest
Research topics from publications: Successive Phase Transitions and Extended Spin-Excitation Continuum in theS=12Triangular-Lattice AntiferromagnetBa3CoSb2<; Yb2Sn2O7: A magnetic Coulomb liquid at a quantum critical point; Competition between the inter- and intra-sublattice interactions inYb2V2O7. Representative work: Using magnetic, thermal, and neutron measurements on single-crystal samples, we show that Ba3CoSb2O9 is a spin-1/2 triangular-lattice antiferromagnet with the c axis as the magnetic easy axis and two magnetic phase transitions bracketing an intermediate up-up-down phase in magnetic field applied along the c axis. A pronounced extensive neutron-scattering continuum above spin-wave excitations, observed below T(N), implies that the system is in close proximity to one of two spin-liquid states that have been predicted for a 2D triangular lattice We report neutron scattering and ac susceptibility measurements on the pyrochlore Yb${}_{2}$Sn${}_{2}$O${}_{7}$. The appearance of magnetic diffuse scattering, low-energy spin excitations, and a nearly temperature-independent relaxation time are signatures that the system enters a short-range-ordered regime with quantum dynamics beneath 2 K. ac susceptibility data further suggest that Yb${}_{2}$Sn${}_{2}$O${}_{7}$ enters a long-range magnetically ordered state below 0.11 K. These results suggest that Yb${}_{2}$Sn${}_{2}$O${}_{7}$ is a ferromagnet with persistent spin dynamics down to 0.05 K. Referencing the phase diagram for Yb pyrochlores, Yb${}_{2}$Sn${}_{2}$O${}_{7}$ is approaching a quan
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Yb<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow/><mml:mn>2</mml:mn></mml:msub></mml:math>Sn<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow/><mml:mn>2</mml:mn></mml:msub></mml:math>O<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow/><mml:mn>7</mml:mn></mml:msub></mml:math>: A magnetic Coulomb liquid at a quantum critical point
Successive Phase Transitions and Extended Spin-Excitation Continuum in the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>S</mml:mi><mml:mo mathvariant="bold">=</mml:mo><mml:mfrac><mml:mn>1</mml:mn><mml:mn>2</mml:mn></mml:mfrac></mml:math>Triangular-Lattice Antiferromagnet<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>Ba</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:msub><mml:mi>CoSb</mml:mi><mml:mn>2</mml:mn></mml:msub><