Extraordinary Photoluminescence and Strong Temperature/Angle-Dependent Raman Responses in Few-Layer Phosphorene

Abstract

Phosphorene is a new family member of two-dimensional materials. We observed strong and highly layer-dependent photoluminescence in few-layer phosphorene (two to five layers). The results confirmed the theoretical prediction that few-layer phosphorene has a direct and layer-sensitive band gap. We also demonstrated that few-layer phosphorene is more sensitive to temperature modulation than graphene and MoS2 in Raman scattering. The anisotropic Raman response in few-layer phosphorene has enabled us to use an optical method to quickly determine the crystalline orientation without tunneling electron microscopy or scanning tunneling microscopy. Our results provide much needed experimental information about the band structures and exciton nature in few-layer phosphorene.

Optical tuning of exciton and trion emissions in monolayer phosphorene

“…Phosphorene is a recently developed two-dimensional (2D) material that has attracted tremendous attention owing to its unique anisotropic manner [1][2][3][4][5][6] , layer-dependent direct band gaps 7,8 , and quasi-onedimensional (1D) excitonic nature 9,10 , which are all in drastic contrast with the properties of other 2D materials, such as graphene 11 and transition metal dichalcogenide (TMD) semiconductors [12][13][14] . Monolayer phosphorene has been of particular interest in exploring technological applications and investigating fundamental phenomena, such as 2D quantum confinement and many-body interactions 9,15 .…”

“…Monolayer phosphorene has been of particular interest in exploring technological applications and investigating fundamental phenomena, such as 2D quantum confinement and many-body interactions 9,15 . However, such unique 2D materials are unstable in ambient conditions and degrade quickly 8,16 . Particularly, monolayer phosphorene is expected to be much less stable than few-layer phosphorene 16 , hence making its identification and characterization extremely challenging.…”

Blue Phosphorene Oxide: Strain-Tunable Quantum Phase Transitions and Novel 2D Emergent Fermions

“…One recent contender in the family that has been receiving significant attention is phosphorene -a single layer of black phosphorus (hereafter referred to as black phosphorene) with an armchair-like puckered lattice structure. [10][11][12] Unlike graphene as a zero-gap semimetal, black phosphorene has a nearly direct bandgap of ~1.5 eV, 12,13 and compared with MoS2 it enjoys a much improved carrier mobility. [10][11][12] Phosphorous is known to be stable in a large family of structures.…”

Field Effect Optoelectronic Modulation of Quantum-Confined Carriers in Black Phosphorus

“…[5][6][7][8][9] Since the first isolation of black phosphorus and demonstration of a field effect device, numerous reports investigating the synthesis and optoelectronic properties of this material have emerged, appropriately summarized in recent reviews. 5,6,[10][11][12] Likewise a number of reports have also appeared on the applications of black phosphorus in fast photodetectors 13 , polarization sensitive detectors, 14 waveguide integrated devices 15 , multispectral photodetectors 16 , visible to near-infrared absorbers 17 and emitters, [18][19][20][21] heterojunction 22 and split gate p-n homojunction photovoltaics 23 , gatetunable van der Waals heterojunctions for digital logic circuits 24,25 and gigahertz frequency transistors in analog electronics 26 . A majority of the studies on both the fundamental optical properties of black phosphorus and applications in optoelectronic devices have explored only the visible frequency range [27][28][29][30] .…”