Roton excitation in overpressurized superfluid <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>He</mml:mi><mml:mprescripts /><mml:none /><mml:mn>4</mml:mn></mml:mmultiscripts></mml:math>
نویسندگان
چکیده
We carry out a theoretical investigation of overpressurized superfluid phases He-4 by means quantum Monte Carlo (QMC) simulations. As function density, we study structural and properties, estimate the energy roton excitation inverting imaginary-time density correlation functions computed QMC, using Maximum Entropy. pressure at which vanishes to be about 100 bars, identify with spinodal i.e., upper limit for existence metastable phase.
منابع مشابه
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2021
ISSN: ['1098-0121', '1550-235X', '1538-4489']
DOI: https://doi.org/10.1103/physrevb.103.014505