qPlus magnetic force microscopy in frequency-modulation mode with millihertz resolution

• Maximilian Schneiderbauer,
• Daniel Wastl and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2012, 3, 174–178, doi:10.3762/bjnano.3.18

• with a single probe. Keywords: hard disc; high-stiffness cantilever; magnetic force microscopy; qPlus; Introduction Ferromagnetism is a collective phenomenon showing a parallel alignment of atomic magnetic dipole moments over macroscopic domains caused by a quantum-mechanical exchange interaction

• used a 41 GB hard disc from MAXTOR with a bit density of approximately 2 Gbit/in2, resulting in a bit size of approximately (200 × 600) nm2. Assuming a rigid tip magnetization in the z-direction, the magnetostatic force is a function of the magnetic moment of the tip and the gradient of the magnetic

• this tip, and with an amplitude of 20 nm in both paths and a lift height of 45 nm, we imaged the bit structure of the hard-disc sample. The topographic image shows the typical surface texture of a hard disc (Figure 2a). The sizeable drift in both images is due to long measuring times, which were

Effect of large mechanical stress on the magnetic properties of embedded Fe nanoparticles

• Srinivasa Saranu,
• Sören Selve,
• Ute Kaiser,
• Luyang Han,
• Ulf Wiedwald,
• Paul Ziemann and
• Ulrich Herr

Beilstein J. Nanotechnol. 2011, 2, 268–275, doi:10.3762/bjnano.2.31

• data storage has been an integral part of computer system technology for many decades and this will most probably remain so in the near future. Over the years, the basic technology of the hard disc, which allows access to magnetic information stored as individual data bits in a magnetic thin film, has