Quantum size effect in thin Cd3As2 films

Żdanowicz, L.; Żdanowicz, W.; Pocztowski, G.

doi:10.1016/0040-6090(75)90125-x

Cited by 17 publications

(7 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previously, Cd 3 As 2 bulk materials, amorphous films [17], nanowires [18] and platelets [19] were prepared by various growth methods, and most magneto-transport measurements so far have focused on Cd 3 As 2 bulk materials. However, few efforts were devoted to thin films [20-22] and nanostructures [18,23], which may exhibit surface phase coherent transport and quantum size limit effect [24][25][26], leading to Aharonov-Bohm oscillations [27] and the exotic quantum Hall insulator states [3]. Importantly, a theoretically predicted TI phase and thickness-dependent quantum oscillations may also eventually emerge when the dimensionality of the system is reduced [3,4].…”

mentioning

confidence: 99%

Thickness-dependent quantum oscillations in Cd₃As₂thin films

et al. 2016

View full text Add to dashboard Cite

Cd 3 As 2 is a new kind of three-dimensional (3D) Dirac semimetal with extraordinary carrier mobility, which can be viewed as '3D graphene'. Theory predicts that Cd 3 As 2 can be driven into a quantum spin Hall insulator with a sizeable band gap by reducing dimensionality. In this letter, we report the systematic growth of undoped Cd 3 As 2 thin films with the thickness of 50∼900 nm by molecular beam epitaxy. The magneto-transport study on these single-crystalline films shows a high mobility in the range of 3.8∼9.1×10 3 cm 2 ·V −1 ·s −1 and a relative low electron concentration of 1∼8×10 17 cm −3 . Significantly, a thickness-induced semimetal-to-semiconductor transition was observed. In contrast with what is expected in the bulk counterpart, the 50 nm-thick Cd 3 As 2 film exhibits semiconducting characteristics, witnessing an emerged bandgap opening when the dimensionality is reduced. Finally, the analyses on the temperature-and angular-dependence of magneto-resistance and Shubnikov-de Hass oscillations reveal a non-trivial to trivial Berry's phase transition that is in connection with the reduced dimensionality. Our results demonstrate that the Cd 3 As 2 thin films with unique electronic structure and high mobility hold promise for Dirac semimetal device applications.Three-dimensional (3D) topological Dirac semimetals (TDSs), such as Na 3 Bi [1, 2] and Cd 3 As 2 [3], have been theoretically predicted and experimentally realized in recent years. These TDSs have unique physical properties originating from 3D massless Dirac fermions. The Dirac nodes are developed due to the touching of valence and conduction bands at discrete points in the reciprocal space. Interestingly, for these 3D Dirac materials, they can be driven into various phases, such as Weyl semimetal [4] and topological insulator (TI) [5, 6] by breaking time reversal or inversion symmetry. Driven by these intriguing physical properties, extensive experiments on angleresolved photoemission spectroscopy (ARPES) [7-10] and scanning tunneling microscopy (STM) [11] were carried out to identify the 3D Dirac fermions in these materials.Cd 3 As 2 is considered to be an excellent 3D TDS due to its chemical stability in air, and it also possesses novel transport phenomena such as ultrahigh mobility [12], large magneto-resistance (MR) [13], non-trivial π Berry's phase of Dirac fermions [14] and chiral anomaly induced negative MR [15,16]. Previously, Cd 3 As 2 bulk materials, amorphous films [17], nanowires [18] and platelets [19] were prepared by various growth methods, and most magneto-transport measurements so far have focused on Cd 3 As 2 bulk materials. However, few efforts were devoted to thin films [20-22] and nanostructures [18,23], which may exhibit surface phase coherent transport and quantum size limit effect [24][25][26], leading to Aharonov-Bohm oscillations [27] and the exotic quantum Hall insulator states [3]. Importantly, a theoretically predicted TI phase and thickness-dependent quantum oscillations may also eventually emerge when th...

show abstract

mentioning

confidence: 99%

Thickness-dependent quantum oscillations in Cd₃As₂thin films

et al. 2016

View full text Add to dashboard Cite

show abstract

“…[24][25][26] However, despite the extensive studies in the past, synthetized Cd 3 As 2 always exhibits n-type conductivity with a high electron concentration, therefore calling for a well-controlled growth scheme and the tunability of carrier density. 14,27 Theory proposed that the chiral anomaly in TDSs can induce nonlocal transport, especially with a large Fermi velocity when the Fermi level, E F , is close to the Dirac nodes.…”

Section: Introductionmentioning

confidence: 99%

Gate-tunable quantum oscillations in ambipolar Cd3As2 thin films

et al. 2015

View full text Add to dashboard Cite

Electrostatic doping in materials can lead to various exciting electronic properties, such as metal-insulator transition and superconductivity, by altering the Fermi level position or introducing exotic phases. Cd 3 As 2 , a three-dimensional (3D) analog of graphene with extraordinary carrier mobility, was predicted to be a 3D Dirac semimetal, a feature confirmed by recent experiments. However, most research so far has been focused on metallic bulk materials that are known to possess ultra-high mobility and giant magneto-resistance but limited carrier transport tunability. Here we report on the first observation of a gate-induced transition from band conduction to hopping conduction in single-crystalline Cd 3 As 2 thin films via electrostatic doping by solid electrolyte gating. The extreme charge doping enables the unexpected observation of p-type conductivity in a ∼50-nm-thick Cd 3 As 2 thin film grown by molecular beam epitaxy. More importantly, the gate-tunable Shubnikov-de Haas oscillations and the temperature-dependent resistance reveal a unique band structure and bandgap opening when the dimensionality of Cd 3 As 2 is reduced. This is also confirmed by our first-principle calculations. The present results offer new insights toward nanoelectronic and optoelectronic applications of Dirac semimetals in general and provide new routes in the search for the intriguing quantum spin Hall effect in low-dimension Dirac semimetals, an effect that is theoretically predicted but not yet experimentally realized.

show abstract

“…The fact that the quantum oscillations of kinetic coefficients are manifested quite distinctly even at room temperature, although it is commonly accepted [5][6][7][8] that any reliable observation of oscillations is possible only at low temperatures, may imply, on the one hand, a rather high degree of structural perfection of the films, and, on the other hand, the possible influence of other (as yet unknown) factors. One can suggest that electron processes accompanying the size quantization may affect the lattice subsystem by stabilizing the structure at critical d values satisfying the quantization conditions.…”

Section: Quantum Size Effects In Pbse-based Superlatticesmentioning

confidence: 99%

“…5 This is why quantum oscillations in the transport properties of thin films with changing d were observed for the first time for semimetallic Bi films, 6 and soon after that for semiconducting compounds InSb and Cd 3 As 2 . 7,8 However, the number of studies related to quantum size oscillations in semiconducting QWs still remains very limited.…”

Section: Introductionmentioning

confidence: 99%

Size Effects in Transport Properties of PbSe Thin Films

Рогачева

Nashchekina

Menshikova

2017

Journal of Elec Materi

View full text Add to dashboard Cite

This paper presents an overview and analysis of our earlier obtained experimental results on the dependences of kinetic properties of single PbSe quantum wells and PbSe-based superlattices on the PbSe layer thickness d. The observed oscillatory character of these dependences is attributed to quantum size effects due to electron or hole confinement in quantum wells. Some general regularities and factors that determine the character of these quantum size effects are established. The influence of the oxidation processes and doping on the d-dependences of the transport properties is revealed. A periodic change in the conductivity type related to quantum size oscillations is detected. It is shown that the experimentally determined values of the oscillation period Dd are in good agreement with the results of theoretical calculations based on the model of a rectangular quantum well with infinitely high walls, taking into account the dependence of the Fermi energy e F on d and the availability of subbands below e F . It is established that the Dd value for the superlattices is practically equal to the Dd value observed for the single PbSe thin film.

show abstract

Quantum size effect in thin Cd3As2 films

Cited by 17 publications

References 3 publications

Thickness-dependent quantum oscillations in Cd₃As₂thin films

Thickness-dependent quantum oscillations in Cd₃As₂thin films

Gate-tunable quantum oscillations in ambipolar Cd3As2 thin films

Size Effects in Transport Properties of PbSe Thin Films

Contact Info

Product

Resources

About

Quantum size effect in thin Cd3As2 films

Cited by 17 publications

References 3 publications

Thickness-dependent quantum oscillations in Cd3As2thin films

Thickness-dependent quantum oscillations in Cd3As2thin films

Gate-tunable quantum oscillations in ambipolar Cd3As2 thin films

Size Effects in Transport Properties of PbSe Thin Films

Contact Info

Product

Resources

About

Thickness-dependent quantum oscillations in Cd₃As₂thin films

Thickness-dependent quantum oscillations in Cd₃As₂thin films