# Spin polarized nonrelativistic fermions in $1+1$ dimensions

## Abstract

We study by Monte Carlo methods the thermodynamics of a spin polarized gas of nonrelativistic fermions in 1 + 1 dimensions. The main result of this work is that our action suffers no significant sign problem for any spin polarization in the region relevant for dilute degenerate Fermi gases. This lack of sign problem allows us to study attractive spin polarized fermions nonperturbatively at spin polarizations not previously explored. For some parameters values we verify results previously obtained by methods which include an uncontrolled step like complex Langevin and/or analytical continuation from imaginary chemical potential. For others, larger values of the polarization, we deviate from these previous results.

- Authors:

- Publication Date:

- Research Org.:
- Univ. of Maryland, College Park, MD (United States); The George Washington University, Washington, DC (United States)

- Sponsoring Org.:
- USDOE

- OSTI Identifier:
- 1471762

- Alternate Identifier(s):
- OSTI ID: 1498928

- Grant/Contract Number:
- FG02-95ER40907; FG02-93ER-40762; FG02-93ER40762

- Resource Type:
- Published Article

- Journal Name:
- Physical Review D

- Additional Journal Information:
- Journal Name: Physical Review D Journal Volume: 98 Journal Issue: 5; Journal ID: ISSN 2470-0010

- Publisher:
- American Physical Society

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS

### Citation Formats

```
Alexandru, Andrei, Bedaque, Paulo F., and Warrington, Neill C. Spin polarized nonrelativistic fermions in 1 + 1 dimensions. United States: N. p., 2018.
Web. doi:10.1103/PhysRevD.98.054514.
```

```
Alexandru, Andrei, Bedaque, Paulo F., & Warrington, Neill C. Spin polarized nonrelativistic fermions in 1 + 1 dimensions. United States. doi:10.1103/PhysRevD.98.054514.
```

```
Alexandru, Andrei, Bedaque, Paulo F., and Warrington, Neill C. Thu .
"Spin polarized nonrelativistic fermions in 1 + 1 dimensions". United States. doi:10.1103/PhysRevD.98.054514.
```

```
@article{osti_1471762,
```

title = {Spin polarized nonrelativistic fermions in 1 + 1 dimensions},

author = {Alexandru, Andrei and Bedaque, Paulo F. and Warrington, Neill C.},

abstractNote = {We study by Monte Carlo methods the thermodynamics of a spin polarized gas of nonrelativistic fermions in 1 + 1 dimensions. The main result of this work is that our action suffers no significant sign problem for any spin polarization in the region relevant for dilute degenerate Fermi gases. This lack of sign problem allows us to study attractive spin polarized fermions nonperturbatively at spin polarizations not previously explored. For some parameters values we verify results previously obtained by methods which include an uncontrolled step like complex Langevin and/or analytical continuation from imaginary chemical potential. For others, larger values of the polarization, we deviate from these previous results.},

doi = {10.1103/PhysRevD.98.054514},

journal = {Physical Review D},

number = 5,

volume = 98,

place = {United States},

year = {2018},

month = {9}

}

DOI: 10.1103/PhysRevD.98.054514

#### Figures / Tables:

_{x}= 61. The extrapolation is done with a quadratic correction formore »

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Figures / Tables found in this record:

*Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.*