Mechanism of superconductivity and electron-hole doping asymmetry in κ-type molecular conductors

We propose a tight binding model study for graphene taking the electron hopping up to third-nearest-neighbors. The graphene placed on different polarized substrates introduces in-equivalences in the two sub-lattices of honeycomb unit cell of graphene. Further the electron/hole doping in graphene enhances the in-equivalence in both the sub-lattices. The Hubbard type Coulomb interaction between the electrons in both sub-lattices generates anti-ferromagnetic (AFM) order in graphene under certain conditions. Zubarev’s Green’s functions method is applied to solve the Hamiltonian. The spins of the electron in the two sub-lattices are assumed to be oriented in opposite directions giving rise to AFM order in the system. The magnetization is calculated from the Green’s functions and computed self-consistently. The effect of the presence of substrates and doping concentrations on magnetization is reported here.

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Low-energy model and electron-hole doping asymmetry of single-layer Ruddlesden-Popper iridates

Physical Review B ◽

10.1103/physrevb.92.085141 ◽

2015 ◽

Vol 92 (8) ◽

Cited By ~ 9

Author(s):

Alexander Hampel ◽

Christoph Piefke ◽

Frank Lechermann

Keyword(s):

Single Layer ◽

Energy Model ◽

Low Energy ◽

Hole Doping ◽

Electron Hole

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Competition between Antiferromagnetic and Superconducting States, Electron-Hole Doping Asymmetry, and Fermi-Surface Topology in High Temperature Superconductors

Physical Review Letters ◽

10.1103/physrevlett.102.027002 ◽

2009 ◽

Vol 102 (2) ◽

Cited By ~ 46

Author(s):

Sandeep Pathak ◽

Vijay B. Shenoy ◽

Mohit Randeria ◽

Nandini Trivedi

Keyword(s):

High Temperature ◽

Fermi Surface ◽

High Temperature Superconductors ◽

Surface Topology ◽

Hole Doping ◽

Electron Hole ◽

Fermi Surface Topology

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Pressure and doping eﬀects on the structural stability of thermoelectric BaAg2Te2

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac3584 ◽

2021 ◽

Author(s):

Hulei Yu ◽

Wen Li ◽

Yanzhong Pei ◽

Yue Chen

Keyword(s):

Transport Properties ◽

Structural Stability ◽

Electrical Transport ◽

Ab Initio Molecular Dynamics ◽

Hole Doping ◽

Electrical Transport Properties ◽

Electron Hole ◽

Doping Effects ◽

Potential Applications ◽

Dynamics Simulations

Abstract Ternary chalcogenides have attracted great attention for their potential applications in thermoelectric devices. Here, we investigate the pressure and doping eﬀects on the structural stability of BaAg2Te2 using ﬁrst-principles calculations. Imaginary frequencies are observed in the calculated phonon dispersions of the reported Pnma structure, indicating that Pnma BaAg2Te2 is lattice dynamically unstable at 0 K. Although the imaginary phonon frequencies are small, we ﬁnd that hydrostatic pressure cannot eﬀectively stabilize the structure. Based on the soft mode at Γ point, a new monoclinic phase with a space group of P21/c is proposed. From ab-initio molecular dynamics simulations, the P21/c phase is predicted to transform to the Pnma phase at a low temperature below 100 K. Electron/hole doping eﬀects on the lattice dynamical stability of the Pnma phase are also studied. It is found that hole doping is superior to electron doping in stabilizing the Pnma phase. Further study on the electrical transport properties of the Pnma phase reveals a higher performance along b axis than that along the other two directions. This work paves an avenue to better understand the structural stability and electrical transport properties of thermoelectric BaAg2Te2.

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Magnetotransport Effects and Electronic Phase Separation in Manganese Sulfides with Electron–Hole Doping

Journal of Experimental and Theoretical Physics ◽

10.1134/s106377612103016x ◽

2021 ◽

Vol 132 (5) ◽

pp. 831-842

Author(s):

O. B. Romanova ◽

S. S. Aplesnin ◽

M. N. Sitnikov ◽

L. V. Udod

Keyword(s):

Phase Separation ◽

Hole Doping ◽

Electron Hole ◽

Electronic Phase Separation ◽

Electronic Phase

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Electric Double Layer Doping of Charge-Ordered Insulators α-(BEDT-TTF)2I3 and α-(BETS)2I3

Crystals ◽

10.3390/cryst11070791 ◽

2021 ◽

Vol 11 (7) ◽

pp. 791

Author(s):

Yoshitaka Kawasugi ◽

Hikaru Masuda ◽

Jiang Pu ◽

Taishi Takenobu ◽

Hiroshi M. Yamamoto ◽

...

Keyword(s):

Phase Transition ◽

Double Layer ◽

Electric Double Layer ◽

Field Effect ◽

Field Effect Transistors ◽

Hole Doping ◽

Hall Resistance ◽

Molecular Conductors ◽

High Tunability ◽

Electronic Phase

Field-effect transistors based on strongly correlated insulators are an excellent platform for studying the electronic phase transition and simultaneously developing phase transition transistors. Molecular conductors are suitable for phase transition transistors owing to the high tunability of the electronic states. Molecular Mott transistors show field-induced phase transitions including superconducting transitions. However, their application to charge-ordered insulators is limited. In this study, we fabricated electric double layer transistors based on quarter-filled charge-ordered insulators α-(BEDT-TTF)2I3 and α-(BETS)2I3. We observed ambipolar field effects in both compounds where both electron and hole doping (up to the order of 1013 cm−2) reduces the resistance by the band filling shift from the commensurate value. The maximum field-effect mobilities are approximately 10 and 55 cm2/Vs, and the gate-induced conductivities are 0.96 and 3.6 e2/h in α-(BEDT-TTF)2I3 and α-(BETS)2I3, respectively. However, gate-induced metallic conduction does not emerge. The gate voltage dependence of the activation energy in α-(BEDT-TTF)2I3 and the Hall resistance in α-(BETS)2I3 imply that the electric double layer doping in the present experimental setup induces hopping transport rather than band-like two-dimensional transport.

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