Abstract
With the continuing miniaturization of semiconductor microelectronics, atomically thin materials are emerging as promising candidate materials for future ultrascale electronics. In particular, the layered transition metal dichalcogenides (TMDs) have attracted a significant amount of attention because of the variety of their electronic properties, depending on the type of transition metal and its coordination within the crystal. Here, we use low-temperature scanning tunneling microscopy (STM) for the structural and electronic phase engineering of the group V TMD niobium diselenide (NbSe2). By applying voltage pulses with an STM tip, we can transform the material crystal phase locally from trigonal prismatic (2H) to octahedral (1T), as confirmed by the concomitant emergence of a characteristic (√13 × √13)R13.9° charge density wave (CDW) order. At 77 K, atomic-resolution STM images of the junction with sublattice detail confirm the successful phase engineering of the material, as we resolve the difference in the Nb coordination evidenced by a slip of the top Se plane. Different 1T-CDW intensities suggest interlayer interactions to be present in 1T-NbSe2. Furthermore, a distinct voltage dependence suggests a complex CDW mechanism that does not just rely on a star-of-David reconstruction as in the case of other 1T-TMDs. Additionally, bias pulses cause surface modifications inducing local lattice strain that favors a one-dimensional charge order over the intrinsic 3 × 3 CDW at 4.5 K for 2H-NbSe2, which can be reversibly manipulated by STM.
| Original language | English |
|---|---|
| Pages (from-to) | 9907-9914 |
| Number of pages | 8 |
| Journal | Chemistry of Materials |
| Volume | 29 |
| Issue number | 23 |
| DOIs | |
| Publication status | Published - 12 Dec 2017 |
Keywords
- Charge density waves
- CDW phase
- waves
Cite this
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Nanoscale Phase Engineering of Niobium Diselenide. / Bischoff, Felix; Auwärter, Willi; Barth, Johannes V.; Schiffrin, Agustin; Fuhrer, Michael; Weber, Bent.
In: Chemistry of Materials, Vol. 29, No. 23, 12.12.2017, p. 9907-9914.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Nanoscale Phase Engineering of Niobium Diselenide
AU - Bischoff, Felix
AU - Auwärter, Willi
AU - Barth, Johannes V.
AU - Schiffrin, Agustin
AU - Fuhrer, Michael
AU - Weber, Bent
PY - 2017/12/12
Y1 - 2017/12/12
N2 - With the continuing miniaturization of semiconductor microelectronics, atomically thin materials are emerging as promising candidate materials for future ultrascale electronics. In particular, the layered transition metal dichalcogenides (TMDs) have attracted a significant amount of attention because of the variety of their electronic properties, depending on the type of transition metal and its coordination within the crystal. Here, we use low-temperature scanning tunneling microscopy (STM) for the structural and electronic phase engineering of the group V TMD niobium diselenide (NbSe2). By applying voltage pulses with an STM tip, we can transform the material crystal phase locally from trigonal prismatic (2H) to octahedral (1T), as confirmed by the concomitant emergence of a characteristic (√13 × √13)R13.9° charge density wave (CDW) order. At 77 K, atomic-resolution STM images of the junction with sublattice detail confirm the successful phase engineering of the material, as we resolve the difference in the Nb coordination evidenced by a slip of the top Se plane. Different 1T-CDW intensities suggest interlayer interactions to be present in 1T-NbSe2. Furthermore, a distinct voltage dependence suggests a complex CDW mechanism that does not just rely on a star-of-David reconstruction as in the case of other 1T-TMDs. Additionally, bias pulses cause surface modifications inducing local lattice strain that favors a one-dimensional charge order over the intrinsic 3 × 3 CDW at 4.5 K for 2H-NbSe2, which can be reversibly manipulated by STM.
AB - With the continuing miniaturization of semiconductor microelectronics, atomically thin materials are emerging as promising candidate materials for future ultrascale electronics. In particular, the layered transition metal dichalcogenides (TMDs) have attracted a significant amount of attention because of the variety of their electronic properties, depending on the type of transition metal and its coordination within the crystal. Here, we use low-temperature scanning tunneling microscopy (STM) for the structural and electronic phase engineering of the group V TMD niobium diselenide (NbSe2). By applying voltage pulses with an STM tip, we can transform the material crystal phase locally from trigonal prismatic (2H) to octahedral (1T), as confirmed by the concomitant emergence of a characteristic (√13 × √13)R13.9° charge density wave (CDW) order. At 77 K, atomic-resolution STM images of the junction with sublattice detail confirm the successful phase engineering of the material, as we resolve the difference in the Nb coordination evidenced by a slip of the top Se plane. Different 1T-CDW intensities suggest interlayer interactions to be present in 1T-NbSe2. Furthermore, a distinct voltage dependence suggests a complex CDW mechanism that does not just rely on a star-of-David reconstruction as in the case of other 1T-TMDs. Additionally, bias pulses cause surface modifications inducing local lattice strain that favors a one-dimensional charge order over the intrinsic 3 × 3 CDW at 4.5 K for 2H-NbSe2, which can be reversibly manipulated by STM.
KW - Charge density waves
KW - CDW phase
KW - waves
UR - http://www.scopus.com/inward/record.url?scp=85038214713&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.7b03061
DO - 10.1021/acs.chemmater.7b03061
M3 - Article
VL - 29
SP - 9907
EP - 9914
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 23
ER -