---
OA_place: repository
OA_type: green
_id: '986'
abstract:
- lang: eng
  text: The many-body localization transition (MBLT) between ergodic and many-body
    localized phases in disordered interacting systems is a subject of much recent
    interest. The statistics of eigenenergies is known to be a powerful probe of crossovers
    between ergodic and integrable systems in simpler examples of quantum chaos. We
    consider the evolution of the spectral statistics across the MBLT, starting with
    mapping to a Brownian motion process that analytically relates the spectral properties
    to the statistics of matrix elements. We demonstrate that the flow from Wigner-Dyson
    to Poisson statistics is a two-stage process. First, a fractal enhancement of
    matrix elements upon approaching the MBLT from the delocalized side produces an
    effective power-law interaction between energy levels, and leads to a plasma model
    for level statistics. At the second stage, the gas of eigenvalues has local interactions
    and the level statistics belongs to a semi-Poisson universality class. We verify
    our findings numerically on the XXZ spin chain. We provide a microscopic understanding
    of the level statistics across the MBLT and discuss implications for the transition
    that are strong constraints on possible theories.
article_number: 041424(R)
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Maksym
  full_name: Serbyn, Maksym
  id: 47809E7E-F248-11E8-B48F-1D18A9856A87
  last_name: Serbyn
  orcid: 0000-0002-2399-5827
- first_name: Joel
  full_name: Moore, Joel
  last_name: Moore
citation:
  ama: Serbyn M, Moore J. Spectral statistics across the many-body localization transition.
    <i>Physical Review B - Condensed Matter and Materials Physics</i>. 2016;93(4).
    doi:<a href="https://doi.org/10.1103/PhysRevB.93.041424">10.1103/PhysRevB.93.041424</a>
  apa: Serbyn, M., &#38; Moore, J. (2016). Spectral statistics across the many-body
    localization transition. <i>Physical Review B - Condensed Matter and Materials
    Physics</i>. American Physical Society. <a href="https://doi.org/10.1103/PhysRevB.93.041424">https://doi.org/10.1103/PhysRevB.93.041424</a>
  chicago: Serbyn, Maksym, and Joel Moore. “Spectral Statistics across the Many-Body
    Localization Transition.” <i>Physical Review B - Condensed Matter and Materials
    Physics</i>. American Physical Society, 2016. <a href="https://doi.org/10.1103/PhysRevB.93.041424">https://doi.org/10.1103/PhysRevB.93.041424</a>.
  ieee: M. Serbyn and J. Moore, “Spectral statistics across the many-body localization
    transition,” <i>Physical Review B - Condensed Matter and Materials Physics</i>,
    vol. 93, no. 4. American Physical Society, 2016.
  ista: Serbyn M, Moore J. 2016. Spectral statistics across the many-body localization
    transition. Physical Review B - Condensed Matter and Materials Physics. 93(4),
    041424(R).
  mla: Serbyn, Maksym, and Joel Moore. “Spectral Statistics across the Many-Body Localization
    Transition.” <i>Physical Review B - Condensed Matter and Materials Physics</i>,
    vol. 93, no. 4, 041424(R), American Physical Society, 2016, doi:<a href="https://doi.org/10.1103/PhysRevB.93.041424">10.1103/PhysRevB.93.041424</a>.
  short: M. Serbyn, J. Moore, Physical Review B - Condensed Matter and Materials Physics
    93 (2016).
date_created: 2018-12-11T11:49:33Z
date_published: 2016-01-29T00:00:00Z
date_updated: 2026-05-20T13:36:19Z
day: '29'
doi: 10.1103/PhysRevB.93.041424
extern: '1'
external_id:
  arxiv:
  - '1508.07293'
fulldoi: https://doi.org/10.1103/PhysRevB.93.041424
intvolume: '        93'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: ' https://doi.org/10.48550/arXiv.1508.07293'
month: '01'
oa: 1
oa_version: Preprint
publication: Physical Review B - Condensed Matter and Materials Physics
publication_identifier:
  eissn:
  - 2469-9969
  issn:
  - 2469-9950
publication_status: published
publisher: American Physical Society
publist_id: '6416'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Spectral statistics across the many-body localization transition
type: journal_article
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
volume: 93
year: '2016'
...
---
OA_place: repository
OA_type: green
_id: '987'
abstract:
- lang: eng
  text: In contrast to bulk FeSe, which exhibits nematic order and low temperature
    superconductivity, highly doped FeSe reverses the situation, having high temperature
    superconductivity appearing alongside a suppression of nematic order. To investigate
    this phenomenon, we study a minimal electronic model of FeSe, with interactions
    that enhance nematic fluctuations. This model is sign problem free, and is simulated
    using determinant quantum Monte Carlo (DQMC). We developed a DQMC algorithm with
    parallel tempering, which proves to be an efficient source of global updates and
    allows us to access the region of strong interactions. Over a wide range of intermediate
    couplings, we observe superconductivity with an extended s-wave order parameter,
    along with enhanced, but short-ranged, q=(0,0) ferro-orbital (nematic) order.
    These results are consistent with approximate weak-coupling treatments that predict
    that nematic fluctuations lead to superconducting pairing. Surprisingly, in the
    parameter range under study, we do not observe nematic long-range order. Instead,
    at stronger coupling an unusual insulating phase with q=(π,π) antiferro-orbital
    order appears, which is missed by weak-coupling approximations.
acknowledgement: We thank S. Gazit for numerous discussions. This research was supported
  by the Gordon and Betty Moore Foundation EPiQS Initiative through Grant No. GBMF4307
  (M.S.), the U.S. Department of Energy, Office of Science, Office of Basic Energy
  Sciences under Grant No. DE-SC0014671 (R.T.S.), and a Simons Investigator grant
  (A.V.).
article_number: '155127'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Philipp
  full_name: Dumitrescu, Philipp
  last_name: Dumitrescu
- first_name: Maksym
  full_name: Serbyn, Maksym
  id: 47809E7E-F248-11E8-B48F-1D18A9856A87
  last_name: Serbyn
  orcid: 0000-0002-2399-5827
- first_name: Richard
  full_name: Scalettar, Richard
  last_name: Scalettar
- first_name: Ashvin
  full_name: Vishwanath, Ashvin
  last_name: Vishwanath
citation:
  ama: 'Dumitrescu P, Serbyn M, Scalettar R, Vishwanath A. Superconductivity and nematic
    fluctuations in a model of doped FeSe monolayers: Determinant quantum Monte Carlo
    study. <i>Physical Review B</i>. 2016;94(15). doi:<a href="https://doi.org/10.1103/PhysRevB.94.155127">10.1103/PhysRevB.94.155127</a>'
  apa: 'Dumitrescu, P., Serbyn, M., Scalettar, R., &#38; Vishwanath, A. (2016). Superconductivity
    and nematic fluctuations in a model of doped FeSe monolayers: Determinant quantum
    Monte Carlo study. <i>Physical Review B</i>. American Physical Society. <a href="https://doi.org/10.1103/PhysRevB.94.155127">https://doi.org/10.1103/PhysRevB.94.155127</a>'
  chicago: 'Dumitrescu, Philipp, Maksym Serbyn, Richard Scalettar, and Ashvin Vishwanath.
    “Superconductivity and Nematic Fluctuations in a Model of Doped FeSe Monolayers:
    Determinant Quantum Monte Carlo Study.” <i>Physical Review B</i>. American Physical
    Society, 2016. <a href="https://doi.org/10.1103/PhysRevB.94.155127">https://doi.org/10.1103/PhysRevB.94.155127</a>.'
  ieee: 'P. Dumitrescu, M. Serbyn, R. Scalettar, and A. Vishwanath, “Superconductivity
    and nematic fluctuations in a model of doped FeSe monolayers: Determinant quantum
    Monte Carlo study,” <i>Physical Review B</i>, vol. 94, no. 15. American Physical
    Society, 2016.'
  ista: 'Dumitrescu P, Serbyn M, Scalettar R, Vishwanath A. 2016. Superconductivity
    and nematic fluctuations in a model of doped FeSe monolayers: Determinant quantum
    Monte Carlo study. Physical Review B. 94(15), 155127.'
  mla: 'Dumitrescu, Philipp, et al. “Superconductivity and Nematic Fluctuations in
    a Model of Doped FeSe Monolayers: Determinant Quantum Monte Carlo Study.” <i>Physical
    Review B</i>, vol. 94, no. 15, 155127, American Physical Society, 2016, doi:<a
    href="https://doi.org/10.1103/PhysRevB.94.155127">10.1103/PhysRevB.94.155127</a>.'
  short: P. Dumitrescu, M. Serbyn, R. Scalettar, A. Vishwanath, Physical Review B
    94 (2016).
date_created: 2018-12-11T11:49:33Z
date_published: 2016-10-17T00:00:00Z
date_updated: 2026-05-20T13:49:33Z
day: '17'
doi: 10.1103/PhysRevB.94.155127
extern: '1'
external_id:
  arxiv:
  - '1512.08523'
fulldoi: https://doi.org/10.1103/PhysRevB.94.155127
intvolume: '        94'
issue: '15'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: ' https://doi.org/10.48550/arXiv.1512.08523'
month: '10'
oa: 1
oa_version: Preprint
publication: Physical Review B
publication_identifier:
  eissn:
  - 2469-9969
  issn:
  - 2469-9950
publication_status: published
publisher: American Physical Society
publist_id: '6413'
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Superconductivity and nematic fluctuations in a model of doped FeSe monolayers:
  Determinant quantum Monte Carlo study'
type: journal_article
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
volume: 94
year: '2016'
...
---
OA_type: closed access
_id: '1742'
abstract:
- lang: eng
  text: The effects of substrate temperature, growth rate, and postgrowth annealing
    on the composition of Ge islands grown on Si(001) were investigated with a combination
    of selective wet chemical etching and atomic force microscopy. A simple kinetic
    model comprising only surface diffusion processes can explain all the experimentally
    observed compositional profiles for pyramid and dome islands grown in the 560-620°C
    range. From this model three-dimensional compositional maps were extracted. By
    performing annealing experiments a change in the composition of the domes was
    observed. This could be explained as the result of the islands' movement induced
    by alloying-driven energy minimization. Also in this case kinetically hindered
    bulk diffusion processes are not needed to explain the experimental observations.
acknowledgement: G. K. acknowledges the financial support of DAAD (Deutscher Akademischer
  Austausch Dienst)
article_processing_charge: No
article_type: original
author:
- first_name: Georgios
  full_name: Katsaros, Georgios
  id: 38DB5788-F248-11E8-B48F-1D18A9856A87
  last_name: Katsaros
  orcid: 0000-0001-8342-202X
- first_name: Giovanni
  full_name: Costantini, Giovanni
  last_name: Costantini
- first_name: Mathieu
  full_name: Stoffel, Mathieu
  last_name: Stoffel
- first_name: Rubén
  full_name: Esteban, Rubén
  last_name: Esteban
- first_name: Alexander
  full_name: Bittner, Alexander
  last_name: Bittner
- first_name: Armando
  full_name: Rastelli, Armando
  last_name: Rastelli
- first_name: Ulrich
  full_name: Denker, Ulrich
  last_name: Denker
- first_name: Oliver
  full_name: Schmidt, Oliver
  last_name: Schmidt
- first_name: Klaus
  full_name: Kern, Klaus
  last_name: Kern
citation:
  ama: Katsaros G, Costantini G, Stoffel M, et al. Kinetic origin of island intermixing
    during the growth of Ge on Si (001). <i>Physical Review B - Condensed Matter and
    Materials Physics</i>. 2005;72(19). doi:<a href="https://doi.org/10.1103/PhysRevB.72.195320">10.1103/PhysRevB.72.195320</a>
  apa: Katsaros, G., Costantini, G., Stoffel, M., Esteban, R., Bittner, A., Rastelli,
    A., … Kern, K. (2005). Kinetic origin of island intermixing during the growth
    of Ge on Si (001). <i>Physical Review B - Condensed Matter and Materials Physics</i>.
    American Physical Society. <a href="https://doi.org/10.1103/PhysRevB.72.195320">https://doi.org/10.1103/PhysRevB.72.195320</a>
  chicago: Katsaros, Georgios, Giovanni Costantini, Mathieu Stoffel, Rubén Esteban,
    Alexander Bittner, Armando Rastelli, Ulrich Denker, Oliver Schmidt, and Klaus
    Kern. “Kinetic Origin of Island Intermixing during the Growth of Ge on Si (001).”
    <i>Physical Review B - Condensed Matter and Materials Physics</i>. American Physical
    Society, 2005. <a href="https://doi.org/10.1103/PhysRevB.72.195320">https://doi.org/10.1103/PhysRevB.72.195320</a>.
  ieee: G. Katsaros <i>et al.</i>, “Kinetic origin of island intermixing during the
    growth of Ge on Si (001),” <i>Physical Review B - Condensed Matter and Materials
    Physics</i>, vol. 72, no. 19. American Physical Society, 2005.
  ista: Katsaros G, Costantini G, Stoffel M, Esteban R, Bittner A, Rastelli A, Denker
    U, Schmidt O, Kern K. 2005. Kinetic origin of island intermixing during the growth
    of Ge on Si (001). Physical Review B - Condensed Matter and Materials Physics.
    72(19).
  mla: Katsaros, Georgios, et al. “Kinetic Origin of Island Intermixing during the
    Growth of Ge on Si (001).” <i>Physical Review B - Condensed Matter and Materials
    Physics</i>, vol. 72, no. 19, American Physical Society, 2005, doi:<a href="https://doi.org/10.1103/PhysRevB.72.195320">10.1103/PhysRevB.72.195320</a>.
  short: G. Katsaros, G. Costantini, M. Stoffel, R. Esteban, A. Bittner, A. Rastelli,
    U. Denker, O. Schmidt, K. Kern, Physical Review B - Condensed Matter and Materials
    Physics 72 (2005).
date_created: 2018-12-11T11:53:46Z
date_published: 2005-11-15T00:00:00Z
date_updated: 2026-08-13T07:46:20Z
day: '15'
doi: 10.1103/PhysRevB.72.195320
extern: '1'
fulldoi: https://doi.org/10.1103/PhysRevB.72.195320
intvolume: '        72'
issue: '19'
language:
- iso: eng
month: '11'
oa_version: None
publication: Physical Review B - Condensed Matter and Materials Physics
publication_identifier:
  eissn:
  - 2469-9969
  issn:
  - 2469-9950
publication_status: published
publisher: American Physical Society
publist_id: '5382'
status: public
title: Kinetic origin of island intermixing during the growth of Ge on Si (001)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 72
year: '2005'
...