Directed transport of suspended ferromagnetic nanoparticles under both gradient and uniform magnetic fields

control of the optical properties of nanoparticles by laser fields

در این پایان نامه، درهمتنیدگی بین یک سیستم نقطه کوانتومی دوگانه(مولکول نقطه کوانتومی) و میدان مورد مطالعه قرار گرفته است. از آنتروپی ون نیومن به عنوان ابزاری برای بررسی درهمتنیدگی بین اتم و میدان استفاده شده و تاثیر پارامترهای مختلف، نظیر تونل زنی(که توسط تغییر ولتاژ ایجاد می شود)، شدت میدان و نسبت دو گسیل خودبخودی بر رفتار درجه درهمتنیدگی سیستم بررسی شده اشت.با تغییر هر یک از این پارامترها، در...

Analysis of a Rigid Ferromagnetic Body under Applied Magnetic Fields

Dynamics of ferrofluid drop deformations under spatially uniform magnetic fields

We systematically study the shape and dynamics of a Newtonian ferrofluid drop immersed in an immiscible, Newtonian and non-magnetic viscous fluid under the action of a uniform external magnetic field. We obtain the exact equilibrium drop shapes for arbitrary ferrofluids, characterize the extent of deviations of the exact shape from the commonly assumed ellipsoidal shape, and analyse the smoothn...

Ferromagnetic vacuum and galactic magnetic fields

Non-abelian gauge theories may have a ferromagnet-like vacuum with a nonzero magnetic field, which also exists at finite temperature. We argue that the formation of the ferromagnet-like vacuum at GUT scales gives rise to a Maxwell magnetic field imprinted on the comoving plasma, and that it is energetically favourable to align the field in different correlation volumes. This results in a cohere...

Uniform excitations in magnetic nanoparticles

We present a short review of the magnetic excitations in nanoparticles below the superparamagnetic blocking temperature. In this temperature regime, the magnetic dynamics in nanoparticles is dominated by uniform excitations, and this leads to a linear temperature dependence of the magnetization and the magnetic hyperfine field, in contrast to the Bloch T(3/2) law in bulk materials. The temperat...