Cyclotron resonance absorption in trilayer graphene

Abstract

Landau Levels (LLs) of ABA-stacked trilayer graphene (TLG) is highly sensitive to the applied transverse electric field ( $E_{\perp}$ ). The energy shifts of LLs can be probed by studying cyclotron resonance (CR) in graphene. Here we demonstrate electrical gate control of CR signals in TLG using dual-gated TLG device. Tuning $E_{\perp}$ while keeping carrier density $n_{\mathrm{e}}$ constant, we observed that the resonance magnetic field of CR signals in TLG were greatly dependent on $E_{\perp}$ . In addition, the experimental data shows transitions between monolayer graphene (MLG)-like LLs and a bilayer graphene (BLG)-like LLs originate from a mixing of those LLs, which is allowed only in the presence of $E_{\perp}$ . The position and its shift of each transition is well reproduced by numerical calculation using tight-binding model, indicating that our data directly reflects the $E_{\perp}$ tunability of the band structure of TLG. ABA-stacked TLG has a great potential for future application as photovoltaic devices capable of external controlling of wavelength.