Surat Tugas untuk presentasi karya ilmiah "Tinjauan Sastra Anak Indonesia Multikultural Berbahasa Inggris: Tema dan Fitur Kunci" yang dipresentasikan dalam rangkaian acara Dies Natalis Fakultas Ilmu Budaya ke-39 pada tanggal 8 Maret 2021 dan diterbitkan dalam Prosiding Seminar Nasional "Peran Ilmu-Ilmu Budaya dalam Pemajuan Budaya" (Editor: Sudarmoko / Novalinda) sebagai penulis pertama. Penerbit: LPPM UNAND PRESS, 8 Maret 2021.

Surat Tugas untuk presentasi karya ilmiah "Tinjauan Sastra Anak Indonesia Multikultural Berbahasa Inggris: Tema dan Fitur Kunci" yang dipresentasikan dalam rangkaian acara Dies Natalis Fakultas Ilmu Budaya ke-39 pada tanggal 8 Maret 2021 dan diterbitkan dalam Prosiding Seminar Nasional "Peran Ilmu-Ilmu Budaya dalam Pemajuan Budaya" (Editor: Sudarmoko / Novalinda) sebagai penulis pertama. Penerbit: LPPM UNAND PRESS, 8 Maret 2021

Melting of a 2D Quantum Electron Solid in High Magnetic Field

The melting temperature ($T_m$) of a solid is generally determined by the pressure applied to it, or indirectly by its density ($n$) through the equation of state. This remains true even for helium solids\cite{wilk:67}, where quantum effects often lead to unusual properties\cite{ekim:04}. In this letter we present experimental evidence to show that for a two dimensional (2D) solid formed by electrons in a semiconductor sample under a strong perpendicular magnetic field\cite{shay:97} ($B$), the $T_m$ is not controlled by $n$, but effectively by the \textit{quantum correlation} between the electrons through the Landau level filling factor $\nu$=$nh/eB$. Such melting behavior, different from that of all other known solids (including a classical 2D electron solid at zero magnetic field\cite{grim:79}), attests to the quantum nature of the magnetic field induced electron solid. Moreover, we found the $T_m$ to increase with the strength of the sample-dependent disorder that pins the electron solid.Comment: Some typos corrected and 2 references added. Final version with minor editoriol revisions published in Nature Physic

Wigner Crystallization in a Quasi-3D Electronic System

When a strong magnetic field is applied perpendicularly (along z) to a sheet confining electrons to two dimensions (x-y), highly correlated states emerge as a result of the interplay between electron-electron interactions, confinement and disorder. These so-called fractional quantum Hall (FQH) liquids form a series of states which ultimately give way to a periodic electron solid that crystallizes at high magnetic fields. This quantum phase of electrons has been identified previously as a disorder-pinned two-dimensional Wigner crystal with broken translational symmetry in the x-y plane. Here, we report our discovery of a new insulating quantum phase of electrons when a very high magnetic field, up to 45T, is applied in a geometry parallel (y-direction) to the two-dimensional electron sheet. Our data point towards this new quantum phase being an electron solid in a "quasi-3D" configuration induced by orbital coupling with the parallel field