# Visualizing Uniaxial-strain Manipulation of Antiferromagnetic

Combining molecular beam epitaxy and in situ angle resolved photoemission spectroscopy (ARPES), we study the ultra thin FeSe films on various substrates. ARPES on FeSe /SrTiO 3 Films and Silicene Xingjiang ZHOU (周兴江) National Lab for Superconductivity Institute of Physics, Chinese Academy of Sciences, Beijing, China 5th Swiss-China Workshop 2015/05/04-05, Brugg, Switzerland Monolayer FeSe Medvedev et al, Nat. Mater 8 630 (2009) Bulk FeSe • T c =9K at ambient pressure ARPES for 2D Materials, Nanomaterials,8, 284 (2018) states and the related nemativity in FeSe. In this paper, we report an ARPES investigation of the low-energy electronic states of FeSe thin films grown on STO substrate. We reveal the existence of Dirac cone band dispersions in FeSe thin films thicker than one unit-cell below the nematic transition temperature. ARPES microscopy measurements of the domain population within the nematic phase of FeSe single crystals. We are able to demonstrate a variation of the domain population density on a scale of a few 10 m while constraining the upper limit of the single High‐temperature superconductivity at the FeSe/SrTiO3 interface Yuan‐Yuan Xiang, Fa wang, DA Wang, Qiang‐Hua Wang, and Dong‐Hai Lee. Phys.

Although ARPES measurements indicated a the distinct pseudogap-like reduction in DOS in the hole pocket above $$T_{\text{c}}$$, 116) no discernible reduction in DOS was observed in STS measurements. 142) The evolutions of the BCS–BEC crossover behavior in FeSe $$_{1-x}$$ S x again suggest that a multiband system exhibits a unique feature that is absent in a single-band system. Recently, in single layer FeSe films grown on SrTiO$_3$ substrate, signs for a new 65 K Tc record are reported. Combining molecular beam epitaxy and in situ angle resolved photoemission spectroscopy (ARPES), we study the ultra thin FeSe films on various substrates.

By probing detwinned crystals with different linear polarizations of their pulsed laser system (250 fs time resolution), they can selectively observe xz and yz orbital electrons. ARPES characterizations of 1UC FeSe/5UC LTO/STO films. a) Schematic diagram of the material structure.

## Effekten av nematisk beställning på fese elektronisk struktur

3. FeSe/STO films. S. Tan, D. L. Feng*, Nature  30 Sep 2020 4.2 Evidence for the crossover in FeSe. 4.2.1 Penetration depth.

### Dikotomi av den elektroniska strukturen och superledningsförmågan

By probing detwinned crystals with different linear polarizations of their pulsed laser system (250 fs time resolution), they can selectively observe xz and yz orbital electrons. ARPES characterizations of 1UC FeSe/5UC LTO/STO films.

The application of a mechanical strain is used to promote the volume 2019-10-02 · However, correlations strongly renormalize the bands compared to electronic structure calculations, and there is no evidence for the expected bulk band inversion. We present here a comprehensive angle resolved photoemission (ARPES) study of FeSeTe as function of photon energies ranging from 15 - 100 eV. 2017-05-05 · Thus the low temperature Fermi surface of FeSe as experimentally determined by ARPES consists of one elliptical hole pocket and one orthogonally-oriented peanut-shaped electron pocket. Our measurements clarify the long-standing controversies over the interpretation of ARPES measurements of FeSe. We report high resolution ARPES measurements of detwinned FeSe single crystals. The application of a mechanical strain is used to promote the volume fraction of one of the orthorhombic domains in the sample, which we estimate to be 80% detwinned.

INTRODUCTION 2012-07-03 · Direct-ARPES and STM Investigation of FeSe Thin Film Growth by Nd:YAG Laser Sandeep Kumar Chaluvadi, Debashis Mondal, Chiara Bigi, Jun Fujii, Rajdeep Adhikari, Regina Ciancio Phase diagram of FeSe 1 − x S x and the suppression of electronic correlations by S substitution. (a) The ARPES map of the high-symmetry cut through top of the Brillouin zone for the tetragonal phase of FeSe 1 − x S x (x = 0, 0.18, 1) at 56–69 eV, together with a calculated slice for FeS in (b). The solid line indicates the cuts used during ARPES experiments. 2015-07-15 · ARPES studies on the monolayer FeSe exhibit a superconducting gap with a size of 15 meV, corresponding to a T c ∼ 55 K , . Based on a series of ARPES measurements to investigate the effect of film thickness on the electron structure, Tan et al. [37] found the FSs of the monolayer FeSe film and the multilayer FeSe film were significantly different ( Fig. 12 ).

The application of a mechanical strain is used to promote the volume fraction of one of the orthorhombic domains in the sample, which we estimate to be 80$\%$ detwinned. We report high resolution ARPES measurements of detwinned FeSe single crystals. The application of a mechanical strain is used to promote the volume fraction of one of the orthorhombic domains in the sample, which we estimate to be 80% detwinned. While the full structure of the electron pockets consisting of two crossed ellipses may be observed in the tetragonal phase at temperatures above 90 Direct-ARPES and STM Investigation of FeSe Thin Film Growth by Nd:YAG Laser Sandeep Kumar Chaluvadi 1, Debashis Mondal 1,2, Chiara Bigi 1,3, Jun Fujii 1, Rajdeep Adhikari 4, Regina Ciancio 1, Alberta Bonanni 4, Giancarlo Panaccione 1, Giorgio Rossi 1,3, Ivana Vobornik 1,* and Pasquale Orgiani 1,5,* Citation: Chaluvadi , S.K.; Mondal, As it is commonly observed from ARPES on the Fe-based superconductors that the gap closes at the superconducting temperature 17,14, Fig. 3c suggests that the single-layer FeSe sample, we measured ARPES has provided suggestions that the N phase of the single-layer FeSe/SrTiO 3 film may be magnetic and the low-temperature form of the multi-layer FeSe/SrTiO 3 films may be in the spin-density-wave state . Direct evidence is needed to pin down their magnetic nature.
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In this Nature paper, T. Shimojima (RIKEN CEMS) et al. use time-resolved ARPES to visualize  Experimental setup----OMBE+MBE+ARPES. 1. Heterostructure Design and in- situ ARPES study. 2.

Here, we provide an overview of the current understanding of the electronic structure of FeSe, focusing in particular on its low-energy electronic structure as determined from angle-resolved photoemission spectroscopy, quantum oscillations, and magnetotransport measurements of single-crystal in bulk FeSe samples [6]. In this wide temperature range, the system shows a marked electron nematicity in transport [7]. Angle-resolved photoemission spectroscopy (ARPES) =L.F. and J.M. contributed equally to this work. *Corresponding author: veronique.brouet@u-psud.fr investigations [8–12] have revealed a 50 meV splitting at This quantitatively accurate model of FeSe is then used to predict a large temperature dependence of the chemical potential within this system, which we confirm via ARPES measurements. We then modify this tight binding model to account for the C4 symmetry breaking effect of the nematic phase of FeSe, which occurs below Ts = 90 K. In fact, high resolution measurements of the electronic structure of FeSe by ARPES at beamline I05 at Diamond have previously made several important experimental contributions to the understanding 2020-01-31 · FeSe is an unusual FeSC that exhibits nematicity without long range magnetic order. On one hand it provides a unique opportunity to disentangle the effect of nematicity on the electronic structure from that of magnetism; while on the other it provides a test case to gauge whether the isolated long range nematic order is qualitatively similar to that of other FeSCs where the two orders are We present a systematic angle-resolved photoemission spectroscopy study of the superconducting gap in FeSe.
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### Selfconsistent Theory of Superconductivity - Department of

Nematic phase: the hole pocket distorts, one elongated electron pocket seen by ARPES. DFT calculation We report high resolution ARPES measurements of detwinned FeSe single crystals. The application of a mechanical strain is used to promote the volume fraction of one of the orthorhombic domains in the sample, which we estimate to be 80% detwinned. While the full structure of the electron pockets consisting of two crossed ellipses may be observed in the tetragonal phase at temperatures above 90 In this paper, to our knowledge, we report the first observation of an insulator–superconductor crossover in the iron-based superconductors by performing systematic angle-resolved photoemission (ARPES) measurements on the single-layer FeSe/SrTiO 3 films at various carrier concentrations. At a very low carrier concentration, the spectral The observation of replica bands in single-unit-cell FeSe on SrTiO3 (STO)(001) by angle-resolved photoemission spectroscopy (ARPES) has led to the conjecture that the coupling between FeSe Phase diagram of FeSe 1 − x S x and the suppression of electronic correlations by S substitution. (a) The ARPES map of the high-symmetry cut through top of the Brillouin zone for the tetragonal phase of FeSe 1 − x S x (x = 0, 0.18, 1) at 56–69 eV, together with a calculated slice for FeS in (b).

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### Angle-Resolved Photoemission Spectroscopy on High - Amazon.se

ARPES measurements were performed at the Advanced Light Source and Synchrotron Radiation Center, using We report results on epitaxial FeSe thin films grown by pulsed laser deposition (PLD) on CaF2 (001) substrates as obtained by exploiting the advantages of an all-in-situ ultra-high vacuum (UHV) laboratory allowing for direct high-resolution surface analysis by scanning tunnelling microscopy (STM), synchrotron radiation X-ray photoelectron spectroscopy (XPS) and angle-resolved photoemission The FeSe superconductor and its related systems have attracted much attention in the iron-based superconductors owing to their simple crystal structure and peculiar electronic and physical properties. The bulk FeSe superconductor has a superconducting transition temperature (Tc) of ~8 K; it can be dramatically enhanced to 37 K at high pressure. 2015-09-08 ARPES and inelastic neutron spectra measured on twinned and detwinned FeSe [15, 46, 66].