论文标题
$ \ mathrm {ti_xo_y}的超导阶段
Superconducting Phase of $\mathrm{Ti_xO_y}$ Thin Films Grown by Molecular Beam Epitaxy
论文作者
论文摘要
我们研究了生长条件与$ \ mathrm {ti_xo_y}的结构和运输特性之间的复杂关系，该薄膜由分子束外延生长。从金属性到超导性和绝缘状态的运输特性通过通过Ti通量速率和O部分压力（$ p_ {ox} $）在（0001）上生长的（0001） - $ \ mathrm {al_2 o_3} $ cubial at 850 $ cubial cubial cubial cubial，通过Ti通量速率有效调整O/Ti的比率来稳定。 $ c- \ mathrm {tio_ {1 \pmδ}} $缓冲层是针对低O/Ti比率的，而Corundum CR-$ \ MathRM {Ti_2 O_3} $ layer在较高的氧化条件下形成。对于C-$ \ MATHRM {TIO_ {1-Δ}} $缓冲层观察到金属性。在c-$ \ $ \ mathrm {tio_ {1-Δ} $ buffer in Intermediate $ p_ {ox} $ p_ {ox} $条件和an impulator-percondator-percondation compondy at 4.5 c（t $ n 4.5 c）中，超导$ \ mathrm {γ-ti_3 o_5} $magnéli阶段可在c-$ \ m artrm {tio_ {1-Δ}} $缓冲液上进行成核。用于85 nm厚的膜。 $ \ mathrm {γ-ti_3 o_5} $的应变松弛随着膜厚度的增加而发生，并且与厚度依赖性相关的t $ _c $相关，以$ \ mathrm {ti_xo_y} $薄膜观察到。
We investigate the complex relationship between the growth conditions and the structural and transport properties of $\mathrm{Ti_xO_y}$ thin films grown by molecular beam epitaxy. Transport properties ranging from metallicity to superconductivity and insulating states are stabilized by effectively tuning the O/Ti ratio via the Ti flux rate and the O partial pressure, $P_{Ox}$, for films grown on (0001)-$\mathrm{Al_2 O_3}$ substrates at 850$^{\circ}$ C. A cubic $c-\mathrm{TiO_{1\pmδ}}$ buffer layer is formed for low O/Ti ratios while a corundum cr-$\mathrm{Ti_2 O_3}$ layer is formed under higher oxidizing conditions. Metallicity is observed for c-$\mathrm{TiO_{1-δ}}$ buffer layers. The superconducting $\mathrm{γ-Ti_3 O_5}$ Magnéli phase is found to nucleate on a c-$\mathrm{TiO_{1-δ}}$ buffer for intermediate $P_{Ox}$ conditions and an insulator-superconducting transition is observed at 4.5 K (T$_C^{onset}=6 K$) for 85 nm thick films. Strain relaxation of the $\mathrm{γ-Ti_3 O_5}$ occurs with increasing film thickness and correlates with a thickness-dependent increase in T$_C$ observed for $\mathrm{Ti_xO_y}$ thin films.
