As a typical penta two-dimensional material and proposed to be potentially synthesized, in this paper we built a two-probe photodetector based on the penta-BP
5
monolayer, and further studied linear ...and elliptical photogalvanic effects in this device. It was found that produced photocurrents in the BP
5
photodetectors mainly show sine relation on double times of the polarized or elliptical angle for the incident light, and the relation can be modulated by the photon energy and polarized angle. Interestingly, due to high asymmetry of the BP
5
monolayer, the pristine BP
5
photodetector generates very high photocurrents, which are even larger than those including vacancy- and substitution-doping, and this result further proved that asymmetry plays a decisive role in the generation of robust photogalvanic effects, instead of introducing impurities to enhance this effect. Furthermore, the linear photogalvanic effect is stronger than the elliptical photogalvanic effect, and the BP
5
photodetectors for the pristine, vacancy- and substitution-doping cases have relatively high extinction ratios showing these BP
5
photodetectors are all polarization-sensitive. In conclude, these results manifest great potential applications of the penta-BP
5
photodetectors on high performance optoelectronics and nanoelectronic devices.
(a) Graphic illustration of the C2P4 photodetector model, (b) top and side views of the C2P4 photodetector.
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•A self-powered photodetector driven by the photogalvanic effect was bulit ...based on the C2P4 monolayer predicted by our group.•The photocurrents produced by the PGE in the C2P4 photodetector mainly show cosine dependence on the polarization angle of incident light, and the vacancy-defects and substitution-doping can increase the magnitude of photocurrents.•The C2P4 photodetector possesses high extinction ratio, showing it is highly desirable for polarization detection applications.
In this paper, we proposed a self-powered photodetector driven by the photogalvanic effect based on the predicted C2P4 monolayer which has excellent electronic and mechanical properties. We focused on the tuning of photogalvanic effect by creating vacancy-defects and substitution doping using the DFT combined with Keldysh nonequilibrium green’s function formalism. We found that the photocurrents produced by the photogalvanic effect mainly show cosine dependence on the polarization angle of incident light, and the vacancy-defects and substitution-doping can increase the magnitude of photocurrents, corresponding to the enhancement of photogalvanic effect in the C2P4 photodetector. Moreover, the C2P4 photodetector possesses high extinction ratio, showing it is highly desirable for polarization detection applications. Our work reveals promising applications of the C2P4 monolayer for self-powered and low energy-consumption photogalvanic effect driven optoelectronics devices.
Side and top views of the (a) armchair and (b) zigzag PSi photodetector irradiated by the polarized light, and θ is the polarization angle. The blue and gray atoms are corresponding to the Si and P ...atoms.
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•A graphene-like honeycombed PSi monolayer has been found by our group with its thermodynamical, dynamical and mechanical stability having been listed.•When the linearly polarized light illuminates on the armchair or zigzag photodetector, due to the C1 symmetry of PSi monolayer the PSi photodetector can directly produce high photocurrents.•The produced photocurrents show the relations cos(2θ) and sin(2θ) on the polarization angle θ for the armchair and zigzag photodetector, respectively.•The vacancy- and substitution-doping in the PSi photodetector can enhance the generated photocurrents.
Using particle swarm optimization methodology for crystal structure prediction and first-principles density functional theory, a graphene-like honeycombed PSi monolayer has been found by our group with its thermodynamical, dynamical and mechanical stability having been listed. To extend the application of the PSi monolayer, the armchair and zigzag photodetector devices based on the photogalvanic effect have been built. When the linearly polarized light illuminates on the armchair or zigzag photodetector, due to the C1 symmetry of PSi monolayer the PSi photodetector can directly produce high photocurrents. In addition, the produced photocurrents show the relations cos(2θ) and sin(2θ) on the polarization angle θ for the armchair and zigzag photodetector, respectively. Moreover, the value of photon energy can effectively influence the distribution of generated photocurrents, namely the relations on the angle θ. Especially, the vacancy- and substitution-doping in the PSi photodetector can enhance the generated photocurrents. These results demonstrated great potential applications of the PSi monolayer on the low energy-consumption optoelectronics devices.
The graphene-like BC3 monolayer has been experimentally prepared. In this paper, based on this BC3 monolayer, we built its armchair and zigzag photodetectors and studied linear and elliptical ...photogalvanic effects (PGEs) in these devices. It was found that produced photocurrents in the armchair and zigzag BC3 photodetectors mainly show cosine and sine relations on double times of linear or elliptical polarized angle, respectively. Moreover, since the decreasing of symmetry from D6H to C2v or Cs at the vacancy- and substitution-doping situations, the photocurrents in the armchair and zigzag BC3 photodetectors increased about 10–100 times, and the photocurrents even may be detected in experiments. Furthermore, the armchair and zigzag BC3 photodetectors are all polarization-sensitive for their high extinction ratios. In view of that the BC3 monolayer has been prepared, our work manifested great potential applications of the PGE-driven BC3 photodetectors in high performance and low energy-consumption optoelectronic and nanoelectronic devices.
In this paper, based on a graphene-like BGe monolayer (Appl. Mater. Interfaces 2021, 13, 29,764–29769), we built the armchair and zigzag photodetectors and studied linear and circular photogalvanic ...effects (PGEs) in two devices. It was found that the produced photocurrents in the armchair and zigzag BGe photodetectors show the cosine and sine relations on double times of polarized angle for the incident light, respectively. Moreover, the vacancy- and substitution-doping can enlarge the generated PGE in two BGe photodetectors by 10–100 times due to the decreasing of symmetry from D3h to C2v. Furthermore, the armchair and zigzag BGe photodetectors are all polarization-sensitive for their high extinction ratios, which are larger than those of photodetectors based on multiple two-dimensional materials. This work manifests great potential applications of the BGe monolayer on PGE-driven photodetectors in high performance and low energy-consumption optoelectronics and nanoelectronic devices.
Nowadays there is considerable interest in the photogalvanic effect in low-dimensional devices. In this work, we built a two-dimensional Bi
2
C-based photodetector and explored the spin-dependent ...photogalvanic effect under linearly polarized light and zero-bias conditions which can produce experimentally observable photoelectron flow. It was discovered that by introducing vacancies and substitution-doping into the Bi
2
C photodetector, the photogalvanic effect could be enhanced by 10–100 times that of a pristine photodetector, which is sufficient to be detected in experiments. Moreover, due to strong spin–orbit interactions, the Bi
2
C photodetector can produce very high spin polarization, even 100% full spin polarization, and pure spin current at a specific incident angle and photon energy, for example in the Bi1-vacancy Bi
2
C photodetector. In addition, the photon energy of incident light can regulate the produced spin photocurrent, which shows considerable anisotropy. Our results highlight the potential of the Bi
2
C photodetector as a versatile device in optoelectronics and spintronics applications.
Graphical Abstract
The photogalvanic effect (PGE) enables the generation of photocurrent at zero bias and without the need of building
p
–
n
junction, showing potential applications in the low-power two-dimensional ...optoelectronics. However, the PGE photocurrent is generally small and high photocurrents are needed which can be used as the photodetector in practice. Therefore in this paper, we built two photodetectors, namely armchair and zigzag photodetectors, based on the Be
2
Al monolayer with its stabilization has been proved, and further studied linear and elliptical PGEs in these devices. It was found that when introducing the vacancy-doping and substitution-doping corresponding to the increasing of asymmetry from
D
6
H
to
D
2
H
or
C
2
V
for the Be
2
Al monolayer, the strength of PGE photocurrents have been considerably enlarged, showing robust PGEs generated in the armchair and zigzag Be
2
Al photodetectors. Moreover, the photocurrents mainly show the relations cos(2
θ
) for the armchair photodetector and sin(2
θ
+
θ
0
) for the zigzag photodetector with their largest strength reaching up to 34.8 and 4.2
a
0
2
/photon, respectively. In addition, results revealed that the linear PGEs were stronger than the elliptical PGEs, and for the circularly polarized light the strength of photocurrents did not change anymore exhibiting the existence of isotropic PGEs. Finally, high extinction ratios exhibited that the armchair and zigzag Be
2
Al photodetectors were all polarization-sensitive. In conclude, these results manifested great potential applications of the Be
2
Al photodetectors on high-performance optoelectronics and nanoelectronic devices.
