Detection of spin polarization in a quantum wire

We demonstrate detection of spin polarization in a quantum wire utilizing a side coupled quantum dot. By applying in-plane magnetic fields, spin split conducting channels are formed and produce spin polarization in the wire. The magnetic fields also create Zeeman split spin levels in the dot and these states are used as a spin polarization detector. Such kind of spin polarization detection with a side coupled quantum dot will operate even in the zero magnetic field by using two-electron singlet and triplet levels.