Quantum Monte Carlo study of systems interacting via long-range interactions mediated by a cavity
Year: 2026
Type: article
Abstract: We study one-dimensional quantum gases in continuous space with cavity-mediated infinite-range interactions using the variational and the diffusion Monte Carlo methods. Starting from the exact two-body solution, we construct a non-translationally invariant Jastrow wave function that accurately captures the spatial structure induced by the cavity field and provides an efficient many-body ansatz for both bosonic and fermionic systems. We analyze properties of three characteristic quantum systems, subject to long-range interactions: (i) ideal Bose gas, (ii) interacting Bose gas, (iii) ideal Fermi gas. In the absence of short-range interactions, we identify a crossover from a stable, weakly modulated phase realized at finite particle number for repulsive interactions to a self-organized state for attractive interactions, marked by clustering, loss of superfluidity, and, at fixed interaction strength, the absence of a thermodynamic limit. Introducing short-range repulsion, either through contact interactions or fermionic statistics, leads to the formation of a mesoscopic gas-like regime that disappears in the thermodynamic limit. A qualitative phase diagram is proposed to illustrate the combined effects of short- and long-range interactions, highlighting the emergence of distinct regimes with characteristic structural properties. Applying the Kac prescription, we obtain a well-defined thermodynamic limit and show that the periodic modulation found for a finite number of particles in the repulsive regime is a finite-size artifact, while the self-organized state survives with its onset shifted to substantially stronger coupling.
Source: Physical Review A
DOI: 10.1103/6jcl-c1gt
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: G1175115578, G121809054, G1301776901, G1568919837, G1855990336, G1990017007, G2064873908, G2092200808, G2262748287, G2309174360, G2660406951, G279363373, G3005324705, G300979063, G3089118260, G34346518, G3480869486, G3780874795, G396237826, G3978510197, G417969858, G4256646345, G425668148, G430777504, G4317403835, G4491547997, G4657404980, G5080475149, G5421974903, G5845768719, G6344349169, G6842759757, G69051668, G702465783, G7084143925, G7454295244, G8036564213, G8489420821, G897484643, G99296377
OpenAlex ID: W7202343784