Mechanically-tunable bandgap closing in 2D graphene phononic crystals
Abstract We present a tunable phononic crystal which can be switched from a mechanically insulating to a mechanically conductive (transmissive) state. Specifically, in our simulations for a phononic lattice under biaxial tension (σ xx = σ yy = 0.01 N m−1), we find a bandgap for out-of-plane phonons...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2023-02-01
|
| Series: | npj 2D Materials and Applications |
| Online Access: | https://doi.org/10.1038/s41699-023-00374-4 |
| _version_ | 1797864571245953024 |
|---|---|
| author | Jan N. Kirchhof Kirill I. Bolotin |
| author_facet | Jan N. Kirchhof Kirill I. Bolotin |
| author_sort | Jan N. Kirchhof |
| collection | DOAJ |
| description | Abstract We present a tunable phononic crystal which can be switched from a mechanically insulating to a mechanically conductive (transmissive) state. Specifically, in our simulations for a phononic lattice under biaxial tension (σ xx = σ yy = 0.01 N m−1), we find a bandgap for out-of-plane phonons in the range of 48.8–56.4 MHz, which we can close by increasing the degree of tension uniaxiality (σ xx/σ yy) to 1.7. To manipulate the tension distribution, we design a realistic device of finite size, where σ xx/σ yy is tuned by applying a gate voltage to a phononic crystal made from suspended graphene. We show that the bandgap closing can be probed via acoustic transmission measurements and that the phononic bandgap persists even after the inclusion of surface contaminants and random tension variations present in realistic devices. The proposed system acts as a transistor for MHz-phonons with an on/off ratio of 105 (100 dB suppression) and is thus a valuable extension for phonon logic applications. In addition, the transition from conductive to isolating can be seen as a mechanical analogue to a metal-insulator transition and allows tunable coupling between mechanical entities (e.g. mechanical qubits). |
| first_indexed | 2024-04-09T22:54:02Z |
| format | Article |
| id | doaj.art-8dff95262f304866b949faf72cc0d45b |
| institution | Directory Open Access Journal |
| issn | 2397-7132 |
| language | English |
| last_indexed | 2024-04-09T22:54:02Z |
| publishDate | 2023-02-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | npj 2D Materials and Applications |
| spelling | doaj.art-8dff95262f304866b949faf72cc0d45b2023-03-22T11:22:45ZengNature Portfolionpj 2D Materials and Applications2397-71322023-02-01711710.1038/s41699-023-00374-4Mechanically-tunable bandgap closing in 2D graphene phononic crystalsJan N. Kirchhof0Kirill I. Bolotin1Department of Physics, Freie Universität BerlinDepartment of Physics, Freie Universität BerlinAbstract We present a tunable phononic crystal which can be switched from a mechanically insulating to a mechanically conductive (transmissive) state. Specifically, in our simulations for a phononic lattice under biaxial tension (σ xx = σ yy = 0.01 N m−1), we find a bandgap for out-of-plane phonons in the range of 48.8–56.4 MHz, which we can close by increasing the degree of tension uniaxiality (σ xx/σ yy) to 1.7. To manipulate the tension distribution, we design a realistic device of finite size, where σ xx/σ yy is tuned by applying a gate voltage to a phononic crystal made from suspended graphene. We show that the bandgap closing can be probed via acoustic transmission measurements and that the phononic bandgap persists even after the inclusion of surface contaminants and random tension variations present in realistic devices. The proposed system acts as a transistor for MHz-phonons with an on/off ratio of 105 (100 dB suppression) and is thus a valuable extension for phonon logic applications. In addition, the transition from conductive to isolating can be seen as a mechanical analogue to a metal-insulator transition and allows tunable coupling between mechanical entities (e.g. mechanical qubits).https://doi.org/10.1038/s41699-023-00374-4 |
| spellingShingle | Jan N. Kirchhof Kirill I. Bolotin Mechanically-tunable bandgap closing in 2D graphene phononic crystals npj 2D Materials and Applications |
| title | Mechanically-tunable bandgap closing in 2D graphene phononic crystals |
| title_full | Mechanically-tunable bandgap closing in 2D graphene phononic crystals |
| title_fullStr | Mechanically-tunable bandgap closing in 2D graphene phononic crystals |
| title_full_unstemmed | Mechanically-tunable bandgap closing in 2D graphene phononic crystals |
| title_short | Mechanically-tunable bandgap closing in 2D graphene phononic crystals |
| title_sort | mechanically tunable bandgap closing in 2d graphene phononic crystals |
| url | https://doi.org/10.1038/s41699-023-00374-4 |
| work_keys_str_mv | AT jannkirchhof mechanicallytunablebandgapclosingin2dgraphenephononiccrystals AT kirillibolotin mechanicallytunablebandgapclosingin2dgraphenephononiccrystals |