形變石墨烯造成高斯場的出現在近幾年是一項非常熱門的題目，也是開啟形變電子學(straintronics)研究領域的主要原因。近期的研究指出，利用掃描穿隧能譜偵測到在石墨烯奈米突起形變點上有非常大的偽磁場，另一方面科學家們也想出各種方式來形變石墨烯來改變其傳輸性質，例如:成長石墨烯在特殊的基板上、熱膨脹錯位。但不能控制的微米尺度形變在裝置(device)應用端始終是一項挑戰，為此我們開發了一項技術可以在雙層的石墨烯上創造一個局部的波紋拉伸形變，令我們可以同時量測平坦及波紋形變的區域，而有趣的是我們發現水平磁場會引發異常負磁阻且只發生在波紋形變區域；此外在給予垂直磁場時，不尋常的量子霍爾效應也出現在波紋形變區域，我們認為這個現象可能跟異常負磁阻有所關連。最後我們推測負磁阻現象可能來自於雙層石墨烯的晶格結構被波紋拉伸形變後所造成不尋常的層間耦合及干擾。

Strain induced gauge field in graphene systems has been extensively studied leading to usher in a new research field named “straintronics”. In previous studies, scanning tunneling spectroscopic measurement observed a huge pseudo magnetic field at strain induced graphene nanobubbles. On the other hand, scientists induce strain in graphene by growing on particular substrate or using thermal mismatch to change transport properties. But, uncontrollable microscale strains are still challenging for device application. Here, we have developed a technique to locally create the corrugating deformation on bilayer graphene, allowing us to investigate flat and corrugation regime simultaneously. Interestingly, the anomalous negative magnetoresistance (NMR) was extracted only in corrugation regime when the in-plane magnetic field (B_ǁ) was applied. Additionally, the unconventional quantum Hall effect which may associate with anomalous NMR occurred in corrugation regime with an out-plane magnetic field (B_⊥). In conclusion, the anomalous NMR may attribute to the unconventional interlayer coupling and interference due to deformation of the crystal lattice structure.

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