REKAYASA SIFAT MAGNETIK MATERIAL SILICENE DAN GERMANENE MELALUI TERMINASI ATOM HIDROGEN: KAJIAN KOMPUTASI BERBASIS DFT (DENSITY FUNCTIONAL THEORY)

Achmad Naufal Rahadi, Prof. Sholihun, S.Si., M.Sc., Ph.D.Sc.

2025 | Skripsi | FISIKA

Telah dilakukan rekayasa sifat magnetik material silicene dan germanene dengan kajian komputasi menggunakan density functional theory.  Rekayasa sifat magnetik dilakukan dengan terminasi hidrogen pada permukaan silicene dan germanene. Terminasi hidrogen dilakukan dengan menambahkan atom hidrogen pada posisi atas (up) dan bawah (down) sehingga setiap material memiliki sembilan variasi. Untuk mengetahui kemunculan sifat magnet akibat terminasi hidrogen, dilakukan kalkulasi density of states untuk majority spin dan minority spin. Untuk setiap variasi, dihitung momen magnet dan energi adsorpsi. Diperoleh hasil bahwa semakin banyak terminasi hidrogen yang tidak simetris, maka semakin besar momen magnet yang terbentuk. Sebaliknya, terminasi hidrogen yang simetris menyebabkan tidak ada momen magnet total yang terbentuk. Diperoleh juga energi adsorpsi yang bernilai negatif pada semua variasi, berkisar antara -12.44 eV hingga -2.04 eV untuk silicene dan -9.85 eV hingga -1,48 eV untuk germanene. Dengan demikian, terminasi hidrogen pada silicene dan germanene sangat sesuai untuk aplikasi peranti magnetik.

Magnetic properties of silicene and germanene have been enhanced with computational studies using density functional theory. Magnetic properties enhanced using hydrogen termination on the surface of silicene and germanene. Hydrogen termination is carried by adding hydrogen atoms in the up and down positions so that each material has nine variations. To determine the appearance of magnetic properties due to hydrogen termination, density of states calculations for majority spin and minority spin are performed. For each variation, the magnetic moment and adsorption energy values are calculated. It was found that the more unsymmetrical hydrogen termination, the greater the magnetic moment induced. Conversely, symmetrical hydrogen termination causes no total magnetic moment to be induced. The adsorption energy is also negative in all variations, ranging from -12.44 eV to -2.04 eV for silicene and -9.85 eV to -1.48 eV for germanene. Thus, hydrogen termination in silicene and germanene is very suitable for magnetic device applications.Magnetic properties of silicene and germanene have been enhanced with computational studies using density functional theory. Magnetic properties enhanced using hydrogen termination on the surface of silicene and germanene. Hydrogen termination is carried by adding hydrogen atoms in the up and down positions so that each material has nine variations. To determine the appearance of magnetic properties due to hydrogen termination, density of states calculations for majority spin and minority spin are performed. For each variation, the magnetic moment and adsorption energy values are calculated. It was found that the more unsymmetrical hydrogen termination, the greater the magnetic moment induced. Conversely, symmetrical hydrogen termination causes no total magnetic moment to be induced. The adsorption energy is also negative in all variations, ranging from -12.44 eV to -2.04 eV for silicene and -9.85 eV to -1.48 eV for germanene. Thus, hydrogen termination in silicene and germanene is very suitable for magnetic device applications.

Kata Kunci : Germanene, hidrogen, momen magnet, silicene, terminasi.