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Wei-Chen Lin, Chiashain Chuang, Chun-Wei Kuo, Meng-Ting Wu, Jie-Ying Lee, Hsin-Hsuan Lee, Cheng-Hsueh Yang, Ji-Wei Ci, Tian-Shun Xie, [Kenji Watanabe](https://orcid.org/0000-0003-3701-8119), [Takashi Taniguchi](https://orcid.org/0000-0002-1467-3105), Nobuyuki Aoki, Jyh-Shyang Wang, Chi-Te Liang

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[Effect of capping on the Dirac semimetal Cd<sub>3</sub>As<sub>2</sub> on Si grown via molecular beam epitaxy](https://mdr.nims.go.jp/datasets/f36a8f0e-da3a-4be5-ab80-144c2b8961ff)

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Effect of capping on the Dirac semimetal Cd3As2 on Si grown via molecular beam epitaxyNanotechnology     PAPER • OPEN ACCESSEffect of capping on the Dirac semimetal Cd3As2on Si grown via molecular beam epitaxyTo cite this article: Wei-Chen Lin et al 2025 Nanotechnology 36 165001 View the article online for updates and enhancements.You may also likeHigh-performance electronic transport inthe plane of 3D type-II Dirac semimetalsYanfeng Ge, Wenhui Wan, Yong Liu et al.-Composition Profile of Zn3As2-Cd3As2InterfaceMasami Nakamura, Motohiro Iwami andKazuo Kawabe-Phonon limited mobility in 3D Diracsemimetal Cd3As2R Amarnath, K S Bhargavi and S SKubakaddi-This content was downloaded from IP address 144.213.253.16 on 11/03/2025 at 01:51https://doi.org/10.1088/1361-6528/adbb74/article/10.1088/1361-648X/aa8162/article/10.1088/1361-648X/aa8162/article/10.1143/JJAP.12.1649/article/10.1143/JJAP.12.1649/article/10.1143/JJAP.12.1649/article/10.1143/JJAP.12.1649/article/10.1143/JJAP.12.1649/article/10.1088/1757-899X/561/1/012030/article/10.1088/1757-899X/561/1/012030https://pagead2.googlesyndication.com/pcs/click?xai=AKAOjsvWqcShpBxQ7jK-ED5shtpRxxGM0CBPyxz2y8Muwnw9cZN0QnOBoUhe35AVcYiJIUWNtf2vuhxFMcGrsRzhE-yaa08EMjMa8sfSNcRpiWUyEXxhxwInSxcbqzHGaUZBQNJo-dnbPrMC8fD4aHvZEQx57vo6-2tiu0XUrqlqvCPKRdS1QuVhb7sirx2i6nI79Z66PJW0Vw1EyIqUp3Yp9g7RFw0cssyftkGQD9UC2iUaWjezbT__UMtaKN_pEdu_Dnw4BbMF5GyXlQGhtUtnVEhY4M8aMCaKh4a3rFwbhVE9rSdU5T7eeH5J13DGiyXep0_ocUAhw1amc_pZmy6PHLO8apYnKKiNfs7Pl6ScR8BL3ks&sig=Cg0ArKJSzPrkANPZIdIp&fbs_aeid=%5Bgw_fbsaeid%5D&adurl=https://www.edinst.com/product/rms1000-raman-microscope/%3Futm_source%3Dnanotechjournal%26utm_medium%3Dcoversheet%26utm_campaign%3Dphysicsworld%26utm_content%3Drms1000NanotechnologyNanotechnology 36 (2025) 165001 (7pp) https://doi.org/10.1088/1361-6528/adbb74Effect of capping on the Dirac semimetalCd3As2 on Si grown via molecular beamepitaxyWei-Chen Lin1,2,3, Chiashain Chuang4,5,∗, Chun-Wei Kuo4, Meng-Ting Wu4,Jie-Ying Lee6, Hsin-Hsuan Lee7, Cheng-Hsueh Yang6, Ji-Wei Ci4, Tian-Shun Xie8,Kenji Watanabe9, Takashi Taniguchi10, Nobuyuki Aoki8, Jyh-Shyang Wang5,7,∗and Chi-Te Liang6,11,12,13,∗1 Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan2 Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan3 Physical Measurement Laboratory, National Institute of Standards and Technology (NIST),Gaithersburg, MD 20899, United States of America4 Department of Electronic Engineering, Chung Yuan Christian University, Taoyuan 320, Taiwan5 Research Centre for Semiconductor Materials and Advanced Optics, Chung Yuan Christian University,Taoyuan 320, Taiwan6 Department of Physics, National Taiwan University, Taipei 106, Taiwan7 Department of Physics, Chung Yuan Christian University, Taoyuan 320, Taiwan8 Department of Materials Science, Chiba University, Chiba 263, Japan9 Research Center for Electronic and Optical Materials, National Institute for Materials Science, Tsukuba305, Japan10 Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba305, Japan11 Centre for Quantum Science and Engineering, National Taiwan University, Taipei 106, Taiwan12 Taiwan Consortium of Emergent Crystalline Materials (TCECM), Taipei 106, Taiwan13 Taiwan Semiconductor Research Institute (TSRI), Hsinchu 300, TaiwanE-mail: chiashain@cycu.edu.tw, jswang@cycu.edu.tw and ctliang@phys.ntu.edu.twReceived 16 January 2025, revised 22 February 2025Accepted for publication 28 February 2025Published 10 March 2025AbstractGiven the promising applications of large magnetoresistance in the Dirac semimetal cadmiumarsenide (Cd3As2), extensive research into Si-compatible Cd3As2 devices is highly desirable. Toprevent surface degradation and oxidation, the implementation of a protection layer on Cd3As2is imperative. In this study, two vastly different protecting layers were prepared on top of twoCd3As2 samples. A zinc telluride layer was grown on top of one Cd3As2 film, giving rise to aten-fold increased mobility, compared to that of the pristine Cd3As2 sample. Interestingly,unusual negative magnetoresistance is observed in the hexagonal boron nitride-capped Cd3As2device when a magnetic field is applied perpendicularly to the Cd3As2 plane. This is in sharp∗Authors to whom any correspondence should be addressed.Original content from this workmay be used under the termsof the Creative Commons Attribution 4.0 licence. Any fur-ther distribution of this work must maintain attribution to the author(s) and thetitle of the work, journal citation and DOI.1 © 2025 The Author(s). Published by IOP Publishing Ltdhttps://doi.org/10.1088/1361-6528/adbb74https://orcid.org/0009-0003-9542-3697https://orcid.org/0000-0002-7677-8121https://orcid.org/0000-0003-3701-8119https://orcid.org/0000-0001-9203-6040https://orcid.org/0000-0003-4435-5949mailto:chiashain@cycu.edu.twmailto:jswang@cycu.edu.twmailto:ctliang@phys.ntu.edu.twhttp://crossmark.crossref.org/dialog/?doi=10.1088/1361-6528/adbb74&domain=pdf&date_stamp=2025-3-10https://creativecommons.org/licenses/by/4.0/Nanotechnology 36 (2025) 165001 W-C Lin et alcontrast to the chiral anomaly that requires a magnetic field parallel to the Cd3As2 plane. Wesuggest that a protection layer on molecular beam epitaxy-grown Cd3As2 should be useful forrealising its great device applications in magnetic sensing.Supplementary material for this article is available onlineKeywords: anomalous negative magnetoresistance, Dirac semimetal, Cd3As2 heterostructure1. IntroductionDepending on the crystal orientation, cadmium arsenide(Cd3As2) can have a Dirac semimetallic phase [1, 2] or atopological insulating phase [3]. A Dirac semimetallic Cd3As2exhibits a pronounced large linear magnetoresistance (LMR)phenomenon under a magnetic field perpendicular to the elec-tric field direction, stemming from its linear band structurearound the Dirac cone within the momentum space [4, 5]and the positive g-factor [6, 7]. Furthermore, with a parallelmagnetic field, negative magnetoresistance (NMR) occurs dueto the formation of the Fermi arc via the surface state [8].Both aforementioned unique properties reveal Cd3As2 withpromising applications in magnetic sensors, random accessmemory (RAM), etc. It is known that 3D Dirac semimetalCd3As2 can support tunable epsilon-near-zero phenomena [9]and plasmonic waveguides [10] in the THz region. At present,there are some attempts to prepare high-quality Cd3As2 on Si(001) substrates [11]. This approach is highly desirable sincesuch Cd3As2 layers are fully compatible with the existing sil-icon CMOS technology. Our approach is somewhat differ-ent as we use a Si (111) substrate for growing Cd3As2 filmsby molecular beam epitaxy (MBE). Importantly, our methodmay ultimately allow us to even combine GaN-based high-power and optoelectronic devices with the 3D Dirac semi-metal and Si CMOS devices since AlN and AlGaN buffer lay-ers can be readily grown on Si (111) so as to prepare high-quality GaN layers [12]. Moreover, Cd3As2 could be dramat-ically affected by water molecules in the ambient atmosphere[13]. Thus, a protection layer on Cd3As2 on Si (111) is highlyimperative.In this study, distinct from the seminal work done by Lygoet al which shows Cd3As2 as a topological insulator on theGaSb substrate [14], our Cd3As2 samples were grown on sil-icon (111) substrates. On the top, zinc telluride (ZnTe) waschosen as one of the protection layers covering the Cd3As2sample owing to the suitable lattice constant compared tothat of Cd3As2. Recently, Prof. Z-M Liao’s group proposeda 2D–3D Dirac van der Waals graphene-Cd3As2 heterostruc-ture device that should be promising for future spintronic elec-tronics due to the interesting interlayer coupling, like chargetransfer, band engineering, and lattice strain and so on [15,16]. Consequently, for the second device, instead of graphene,we transferred ‘white graphene’—hexagonal boron nitride(h-BN) flake as a ‘modulation’ on Cd3As2 Hall bar centralchannel on Si substrate as new 2D–3D van der Waals het-erostructure device. With a light penetrative protection layer,the h-BN flake on Cd3As2 device becomes an ideal platformfor testing the chiral light amplification [17] and probing thehelicity-dependent photocurrent [18]. Furthermore, the cap-ping protection idea may prove vital for topological nodal linesemimetals [19].Note that the linear band structure of the Dirac cone andWeyl nodes are topologically protected by the C4 crystallinesymmetry because of the three-dimensional nature [20, 21].Therefore, with the protection layers on top, both the ZnTeand h-BN protected Cd3As2 samples still retain theWeyl semi-metallic properties evidenced by the notable NMR in a paral-lel magnetic field. Moreover, the ZnTe/Cd3As2 device mani-fests a significant enhancement inmobility by an order ofmag-nitude, suggesting the efficacy of the ZnTe protective layer inpreserving the integrity of Cd3As2. Conversely, although themobility in the h-BN flake on Cd3As2 device only increasesby a factor of three compared to that of the pristine Cd3As2device, an unconventional NMR behaviour under a perpendic-ular magnetic field arises. We discuss a possible mechanismleading to this unexpected behaviour and show the improv-ing characteristics of the protection layer-capped Cd3As2 withpromising applications.2. ResultsOur experiments were performed on the Cd3As2 films grownon silicon substrates both with and without protection layers asshown in figure 1. The Cd3As2 layer was grown via the MBEtechnique, employing a silicon (111) substrate with an approx-imately 20 nm-thick-cadmium zinc telluride (CdZnTe) bufferlayer. The thin CdZnTe buffer layer served to effectivelymitig-ate the inherent lattice mismatch between Cd3As2 and the sil-icon substrate (seeMethods). All these samples are compatiblewith existing Si CMOS technology, which is useful for poten-tial device applications and integration with Si-based devicessuch as Si photonics [22–24], MOSFETs [24–27], and Si-based quantum information [28–30] and quantum processing[30–32]. The orientation of the Cd3As2 has been confirmedin the (112) direction via the x-ray diffraction (XRD) res-ult (figure S1) which possesses the Dirac semi-metallic phase[33–39]. Moreover, the XRD data shows a piece of evid-ence that there exists a strain affecting the lattice at the inter-face because of a large lattice mismatch which reaches 68%between Cd3As2 and the h-BN capping layer (see supplement-ary section 1), where the latticemismatch betweenCd3As2 andZnTe is 3.4% which can be negligible [35].2https://10.1088/1361-6528/adbb74Nanotechnology 36 (2025) 165001 W-C Lin et alFigure 1. Schematics of the devices. (a) A pristine Cd3As2 sample, (b) a Cd3As2 sample with a ZnTe layer encapsulated, and (c) a Cd3As2sample with a multilayer h-BN flake on top serving as a protective layer. Note that due to the limited size of the exfoliated h-BN, the areacovered by h-BN is limited.Figure 2. The characteristics of large MR. (a) The magnitude of the pristine Cd3As2 device reaches 12% at 5.7 K under 1000 mT. (b) TheZnTe/Cd3As2 device shows approximately 5 time of magnitude larger than the pristine Cd3As2 device indicating that ZnTe as a suitableprotection layer for Cd3As2.2.1. ZnTe-encapsulated Cd3As2A 10 nm-thick-ZnTe protection layer was chosen due to itsclosely matched lattice constant compared to that of Cd3As2.The ZnTe protection layer was immediately grown at the samesubstrate temperature after completing the Cd3As2 layer forone minute, forming an initial layer which is about 1–2 nmthick. Growth is then paused, and the substrate temperatureis raised to 230 ◦C before resuming ZnTe growth for sevenminutes. This process results in a total ZnTe thickness ofapproximately 10 nm, including the initial low-temperaturelayer. This approach is necessary because the optimal substratetemperature for ZnTe epitaxy is 100 ◦C higher compared tothat of Cd3As2. If ZnTe were grown with the same temperat-ure which was used for Cd3As2, the crystalline quality wouldbe significantly affected. However, directly increasing the sub-strate temperature while the Cd3As2 surface is exposed wouldcause degradation. As a result, a thin ZnTe layer is first grownat the same temperature as Cd3As2, providing a protective cov-ering. The Ag contacts are deposited after the ZnTe protectionlayer is grown (see supplementary section 3).As depicted in figure 2(b), the ZnTe/Cd3As2 device demon-strates significantly large LMR, reaching up to 55% at1000 mT and 6.2 K, surpassing that in the pristine Cd3As2device with a value of 12% at 1000 mT at 5.7 K (figure 2(a)).This highlights potential applications of the ZnTe/Cd3As2device in RAM and magnetic sensors. Additionally, the ZnTeprotection layer on Cd3As2 diminishes the effectiveness ofvacuum annealing (see supplementary section 4), pointing outthe exceptional insulating property of ZnTe.Moreover, a significantly low carrier density and highmobility in the ZnTe/Cd3As2 device exhibit ZnTe itself as apromising protection layer which greatly improves the elec-trical properties of the Cd3As2 device (figure 3(b)). Themobility of the ZnTe/Cd3As2 device shows higher magnitudenot only compared to the graphene/Cd3As2 heterostructuredevice (µ≈ 1.3× 104 cm2V−1s−1) [15] but also to the h-BN flake on Cd3As2 device (figure 3(c)). This underscoresthe advantage of selecting a capping layer with a lattice con-stant comparable to that of Cd3As2 for optimal device per-formance. The observed vastly different temperature depend-ence of mobility and carrier density between pristine Cd3As23Nanotechnology 36 (2025) 165001 W-C Lin et alFigure 3. Carrier density and mobility modification via protection layers after vacuum anneal at 100 ◦C for 10 s. (a) The carrier density(mobility) of the pristine Cd3As2 device shows roughly unchanged compared to those of the other two devices. (b) and (c) In contrast, theZnTe/Cd3As2 device and the h-BN flake on Cd3As2 device show a different trend compared to the pristine Cd3As device where the carrierdensity (mobility) decreases (increases) while the temperature decreases. However, the ZnTe protection layer renders the vacuum annealingless effective. The pristine Cd3As2 device manifests the highest carrier density and the lowest mobility amongst the three Cd3As2 devices atthe lowest temperature. These characterizations point out that the insulating protection layers significantly enhance the electrical propertiesof the underlying Cd3As2.layer and its ZnTe and h-BN capped counterparts can beexplained in the following. In capped films, the carrier dens-ity appears to increase with increasing temperature. This maybe ascribed to charge trapping effect, which can be observedin graphene on SiC [40]. The capped Cd3As2 devices showmetallic behaviour in the sense that the mobility decreaseswith increasing temperature (electron-phonon scattering). Incontrast, the pristine Cd3As2 layer shows weakly insulatingbehaviour where dR/dT < 0 since the amount of disorder isstrong due to molecular absorbates on the Cd3As2 surface.Consequently, the mobility increases slightly with increasingtemperature.The NMR depicted in figure 4(a) highlights the emer-gence of the chiral anomaly as time reversal symmetry breaksdue to an external magnetic field parallel to the directionof current flow in the ZnTe/Cd3As2 device. Furthermore,the angle-dependent MR measurements (figure 4(b)) providecompelling evidence of the occurrence of the chiral anomaly[21, 41, 42]. For T > 75 K, the crossover from positive tonegative MR diminishes as the chiral anomaly is expected tobecome weaker with increasing temperature [21]. This tem-perature is significantly lower than the transition temperatureTc ≈ 234.5 K for which there is a crossover from metallic(dR/dT > 0) to weakly insulating behaviour (dR/dT < 0) (sup-plementary figure 4(b)). Our results thus suggest that the zero-field metallic behaviour (dR/dT > 0) does not guarantee thechiral anomaly.2.2. H-BN flake on Cd3As2High-quality h-BN flakes were mechanically exfoliated andstacked onto the Cd3As2 surface by a standard dry trans-fer technique (see Methods). The inset of figure 5(a) illus-trates slightly asymmetric MR under perpendicular magneticfields in opposite directions. The unintended mixing of thelongitudinal resistivity with the Hall resistivity may lead to theobserved asymmetric MR [43]. For simplicity, only the posit-ive magnetic field data will be presented in the subsequent partof our manuscript.Rock-solid evidence of the chiral anomaly, shown as the redcurve in figure 5(b), is exhibited in the h-BN flake on Cd3As2device. Figure 5(a) shows anomalous NMR in a perpendicularmagnetic field at various temperatures, a phenomenon distinctfrom the chiral anomaly that requires the assistance of a mag-netic field parallel to the current flow direction. The anomalousNMR is attributed to the transition fromweak anti-localizationto weak localization effect (see supplementary section 6) ren-dering from the spatial inversion symmetry breaking due tothe strain-gradient on Cd3As2 central channel so as to induce atopological transition [16, 44]. This picture is consistent withshifted Cd3As2 peaks observed in the XRD data (figure S1).The observed magnetoresistance in our h-BN capped Cd3As2is interesting. Although we cannot pinpoint the exact underly-ing mechanism, we speculate that the interface interaction/ef-fect should play an important role in this. Such an interfaceeffect plays a role in the spin-related Khosla–Fischer typeMR, i.e. an interesting, similar PMR/NMR/PMR crossover isobserved in ferromagneticα-Fe2O3 nanosheet grown onMoS2[45].From the angle-dependent MR (figure 5(b)), the negat-ive response tends to be more pronounced as the magneticfield direction aligns perpendicularly to the current direction,providing convincing evidence of the anomalous NMR in theh-BN flake on the h-BN flake on Cd3As2 device. The afore-mentioned observations underscore the advantages of utiliz-ing the h-BN flake as a protection layer and show promisingapplications of the h-BN flake on Cd3As2 device. Please notethat the carrier densities are different between figures 5(a) and(b) because the measurements were performed in differentthermal cycles.4Nanotechnology 36 (2025) 165001 W-C Lin et alFigure 4. The chiral anomaly evidenced by the NMR observed in the ZnTe/Cd3As2 device. (a) The persistence of NMR under a parallelmagnetic field at elevated temperatures, particularly at room temperature, suggests the robust presence of the chiral anomaly in theZnTe/Cd3As2 device. (b) MR plotted with different tilted angles at 6 K. The magnitude of MR decreases while the magnetic field angle tiltsfrom perpendicular (90◦) to parallel (0◦) direction.Figure 5. MR in the h-BN flake on Cd3As2 device. (a) NMR under a perpendicular magnetic field. As the temperature increases, thenegative behaviour diminishes. The inset shows the symmetrical MR from −1000 mT to 1000 mT. (b) Angle-dependent on the MR at 6 K.The magnitude of the negative response intensifies as the magnetic field direction shifts from parallel (0◦) to perpendicular (90◦) orientation.3. DiscussionIn contrast to the pristine Cd3As2 device, the ZnTe/Cd3As2and the h-BN flake on Cd3As2 device both demonstrate mobil-ity enhancements. Notably, the ZnTe/Cd3As2 device showsan order of magnitude increase. Such a ten-fold mobilityenhancement is mostly ascribed to the almost lattice-matchedZnTe layer (with Cd3As2), which improves the interface/crys-tal quality. Moreover, the ZnTe protection layer places anymolecular adsorbates far away from the actual active Cd3As2layer, thereby decreasing electron-impurity scattering. In thecase of h-BN capped Cd3As2, the large lattice mismatchbetween h-BN and Cd3As2 introduces strain. Therefore, themobility enhancement is lower compared with that of its ZnTecapped counterpart. Furthermore, the ZnTe/Cd3As2 deviceexhibits a significant increase in the LMR which surpasses themagnitude shown in the pristine Cd3As2. These improvementsstrongly suggest the advantage of selecting a capping layerwith a closelymatched lattice constant. Interestingly, the h-BNflake on Cd3As2 device presents an anomalous NMR beha-viour in a perpendicular magnetic field which is attributed tothe strain-gradient-induced breaking of spatial inversion sym-metry due to significant lattice mismatch, triggering a topo-logical transition in Cd3As2. In summary, our findings under-score the potential of capping Cd3As2 on silicon substrates toenhance device performance and enable novel magnetoresist-ance effects. Therefore, optimizing with various capping lay-ers could prove pivotal for subsequent studies in the future.4. Methods4.1. Cd3As2 film growthFollowing the fabrication procedures in [35], our Cd3As2samples were grown on a Si (111) substrate by MBE. Thequalities of our Cd3As2 samples were optimized by the XRD5Nanotechnology 36 (2025) 165001 W-C Lin et alimage shown in the supplementary section 1. We replacedthe additional buffer layer of ZnTe with CdZnTe to minim-ize the lattice mismatch from 3.4% to around 1% at the inter-face between the buffer layer and Cd3As2. The ZnTe protec-tion layer was grown after the annealing process.4.2. Cd3As2 Hall barThe Hall bar configurations of the pristine Cd3As2 and an h-BN flake on Cd3As2 samples were shaped by reactive ion etch-ing with 10 sccm CF4 and 10 sccm Ar introduced for 5 min.The average thickness of Cd3As2 film on the Hall bar regionis 175 nm (see figure S3).4.3. H-BN dry transfer techniqueWe employed a standard dry transfer technique based on theconcept described in Wang et al [46]. Firstly, polycarbon-ate (PC) was placed on a homemade polydimethylsiloxanesubstrate. Subsequently, the PC was used to pick up the h-BN flake from the SiO2/Si substrate. Afterwards, the h-BNflake was released onto the central region of the Cd3As2 with aHall bar configuration by heating up the transfer stage. Duringthis process, the PC was melted and left on the h-BN flake onCd3As2 device. Finally, chloroform was utilized to clean thePC residual.4.4. CharacterizationsThe four-terminal measurements were performed to eliminatethe contact resistance in a closed cycle cryostat and equippedwith a 1 T magnet with rotational field angles.Data availability statementThe data that support the findings of this study are availableupon reasonable request from the authors.AcknowledgmentThis work was funded by the Ministry of Scienceand Technology (MOST) and the National Science andTechnology Council (NSTC), Taiwan (Grant Nos: NSTC110-2112-M-033-009-MY3, NSTC 112-2221-E-033-040,NSTC 113-2112-M-033-013, NSTC 113-2221-E-033-023,and NSTC 113-2112-M-002-034-MY3). CC acknowledgesthe Higher Education Sprout Project in Chung Yuan ChristianUniversity which allowed him to visit sister university -Chiba University, Japan for supporting this topic. KW and TTacknowledge support from JSPS KAKENHI (Grant Numbers19H05790, 20H00354 and 21H05233).ORCID iDsWei-Chen Lin https://orcid.org/0009-0003-9542-3697Chiashain Chuang https://orcid.org/0000-0002-7677-8121Kenji Watanabe https://orcid.org/0000-0003-3701-8119Nobuyuki Aoki https://orcid.org/0000-0001-9203-6040Chi-Te Liang https://orcid.org/0000-0003-4435-5949References[1] Li C-Z, Li J-G, Wang L-X, Zhang L, Zhang J-M, Yu D andLiao Z-M 2016 Two-carrier transport induced Hall anomalyand large tunable magnetoresistance in Dirac semimetalCd3As2 nanoplates ACS Nano 10 6020–8[2] Ouyang W, Lygo A C, Chen Y, Zheng H, Vu D, Wooten B L,Liang X, Heremans J P, Stemmer S and Liao B 2024Extraordinary thermoelectric properties of topologicalsurface states in quantum-confined Cd3As2 thin films Adv.Mater. 36 2311644[3] Munyan S, Rashidi A, Lygo A C, Kealhofer R and Stemmer S2023 Edge channel transmission through a quantum pointcontact in the two-dimensional topological insulatorcadmium arsenide Nano Lett. 23 5648[4] Wang C and Lei X 2012 Linear magnetoresistance on thetopological surface Phys. 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