Electron-hole asymmetry in the electron-phonon coupling in top-gated phosphorene transistor

Chakraborty, Biswanath; Gupta, Sanjay; Singh, Anjali; Kuiri, Manabendra; Kumar, C. N.; Muthu, D. V. S.; Das, Anindya; Waghmare, U. V.; Sood, Anil K.

doi:10.1088/2053-1583/3/1/015008

Cited by 24 publications

(32 citation statements)

References 47 publications

(96 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Jing et al [9] based on DFT calculations, report that TCNE withdraws 0.40 electrons from phosphorene while TTF donates 0.15 electrons. These resultsd iffer from the report of Chakraborty et al [10] who examined Ramans cattering of phosphorene in an electrochemically top-gated field effect transistor.T hese workers find that the Raman A g phonons are more affected by electrons than holes. Furthermore, the B g band was insensitive to electrochemical doping.…”

supporting

confidence: 73%

Doping Phosphorene with Holes and Electrons through Molecular Charge Transfer

et al. 2017

View full text Add to dashboard Cite

An important aspect of phosphorene, the novel two-dimensional semiconductor, is whether holes and electrons can both be doped in this material. Some reports found that only electrons can be preferentially doped into phosphorene. There are some theoretical calculations showing charge-transfer interaction with both tetrathiafulvalene (TTF) and tetracyanoethylene (TCNE). We have carried out an investigation of chemical doping of phosphorene by a variety of electron donor and acceptor molecules, employing both experiment and theory, Raman scattering being a crucial aspect of the study. We find that both electron acceptors and donors interact with phosphorene by charge-transfer, with the acceptors having more marked effects. All the three Raman bands of phosphorene soften and exhibit band broadening on interaction with both donor and acceptor molecules. First-principles calculations establish the occurrence of charge-transfer between phosphorene with donors as well as acceptors. The absence of electron-hole asymmetry is noteworthy.

show abstract

supporting

confidence: 73%

Doping Phosphorene with Holes and Electrons through Molecular Charge Transfer

et al. 2017

View full text Add to dashboard Cite

show abstract

“…As suggested by a recent work, the absence of a shift in frequencies as well as full-widths at half-maximum (see Figure S2.1) rules out any n-type doping in the antidot lattice but is inconclusive toward the presence of p-type doping. 83 Furthermore, this result indicates the structure is likely free of any strain since stretching- and compression-induced Raman frequency shifts up to 11 cm −1 /(% strain) are expected in both phosphorene and few-layer BP. 84,85 We also note that across samples the

A_{g}^{1} : A_{g}^{2}

intensity ratio ( i.e ., the ratio of peak heights) remains between 0.5 and 0.6 from pristine to antidot regions, excluding the likelihood of thinning or oxidation due to atmospheric exposure or patterning.…”

Section: Resultsmentioning

confidence: 82%

Periodic Arrays of Phosphorene Nanopores as Antidot Lattices with Tunable Properties

Cupo

Das²,

Chien³

et al. 2017

ACS Nano

View full text Add to dashboard Cite

A tunable band gap in phosphorene extends its applicability in nanoelectronic and optoelectronic applications. Here, we propose to tune the band gap in phosphorene by patterning antidot lattices, which are periodic arrays of holes or nanopores etched in the material, and by exploiting quantum confinement in the corresponding nanoconstrictions. We fabricated antidot lattices with radii down to 13 nm in few-layer black phosphorus flakes protected by an oxide layer and observed suppression of the in-plane phonon modes relative to the unmodified material via Raman spectroscopy. In contrast to graphene antidots, the Raman peak positions in few-layer BP antidots are unchanged, in agreement with predicted power spectra. We also use DFT calculations to predict the electronic properties of phosphorene antidot lattices and observe a band gap scaling consistent with quantum confinement effects. Deviations are attributed primarily to self-passivating edge morphologies, where each phosphorus atom has the same number of bonds per atom as the pristine material so that no dopants can saturate dangling bonds. Quantum confinement is stronger for the zigzag edge nanoconstrictions between the holes as compared to those with armchair edges, resulting in a roughly bimodal band gap distribution. Interestingly, in two of the antidot structures an unreported self-passivating reconstruction of the zigzag edge endows the systems with a metallic component. The experimental demonstration of antidots and the theoretical results provide motivation to further scale down nanofabrication of antidots in the few-nanometer size regime, where quantum confinement is particularly important.

show abstract

“…It is an elemental semiconductor with direct band gap of ∼0.3 eV. Recently there is revival of interest in BP from the prospective of a layered material which allows us to study the exciting properties of a mono and few layers of BP [1][2][3][4][5][6][7][8] . It is found that the band gap depends on the thickness of its film: 0.3eV for thickness > 4nm and 1.2 eV for single layer thick BP 9 .…”

Section: Introductionmentioning

confidence: 99%

Raman anomalies as signatures of pressure induced electronic topological and structural transitions in black phosphorus: Experiments and theory

et al. 2017

Self Cite

View full text Add to dashboard Cite

We report high pressure Raman experiments of Black phosphorus (BP) up to 24 GPa. The line widths of first order Raman modes A 1 g , B2g and A 2 g of the orthorhombic phase show a minimum at 1.1 GPa. Our first-principles density functional analysis reveals that this is associated with the anomalies in electron-phonon coupling at the semiconductor to topological insulator transition through inversion of valence and conduction bands marking a change from trivial to nontrivial electronic topology. The frequencies of B2g and A 2 g modes become anomalous in the rhombohedral phase at 7.4 GPa, and new modes appearing in the rhombohedral phase show anomalous softening with pressure. This is shown to originate from unusual structural evolution of black phosphorous with pressure, based on first-principles theoretical analysis.

show abstract

Electron-hole asymmetry in the electron-phonon coupling in top-gated phosphorene transistor

Cited by 24 publications

References 47 publications

Doping Phosphorene with Holes and Electrons through Molecular Charge Transfer

Doping Phosphorene with Holes and Electrons through Molecular Charge Transfer

Periodic Arrays of Phosphorene Nanopores as Antidot Lattices with Tunable Properties

Raman anomalies as signatures of pressure induced electronic topological and structural transitions in black phosphorus: Experiments and theory

Contact Info

Product

Resources

About