Do Electron Holes Have Spin Angular Momentum?

[Goalie33]

Do holes (i.e. electron holes) have spin angular momentum like electrons do? Thanks for any insight you can give and if you can recommend any literature on the mater that would be great!
Thanks!

 

[Drakkith]

I don't believe a hole is a physical object, but simply a spot where an electron used to be. It has no physical properties as far as I understood.

 

[Goalie33]

Yes, but they can be modeled as particles with a charge and an effective mass, so after that my next thought was spin. Can anyone else weigh in on the matter?

 

[Vanadium 50]

Yes, they can have spin.

 

[Goalie33]

V50, could you elaborate or recommend something for me to read?

 

[Chopin]

Are we talking about holes in the sense of semiconductor physics (an empty spot in the valence band of an atom), or holes in the sense of antiparticles (the "void in the Dirac Sea" idea)? I'm not enormously familiar with the former, but the latter can be explicitly modeled as particles in all ways, so they have spin just like normal electrons do.

Even in the case of the former, I would surmise that it must be able to have spin, just by a conservation argument. A hole and an electron can come together and annihilate each other, leaving nothing behind, right? An electron has spin, which means it has a definite amount of angular momentum. If a hole had no spin, then after annihilation, there would be less angular momentum in the universe than there was before. Therefore, we can conclude that not only does a hole have spin, but it must also be equal and opposite to that of the electron if angular momentum is to be conserved.

 

[Goalie33]

For the record I was talking about semiconductors.

 

[Shawakaze]

I don't think a hole is a physical entity for it to even be associated to physical property. Its strictly an idea of absence of an electron. Can nothing have a property such as spin? Yes we speak of holes having positive charge, but we are strictly speaking of an absence of an electron in a very specified location.

 

[sokrates]

Holes can be thought of electrons with negative effective mass, and they DO have SPIN.

It is mathematically more convenient to count "absence of electrons" rather than the nearly full bands - because valence bands of materials are typically full of electrons.

But you could think of holes as particles, and there's nothing wrong with that.Ga Mn As is one material that has spin-polarized "holes" in it, so that can be a good example for you.

But fundamentally, there's no difference between spin of an electron or an hole. It's the same thing. So I wouldn't even say they "can" have spin, instead they Do have spins but most of the time these are paired and no magnetic properties are observed .

 

[Cthugha]

Holes can be thought of electrons with negative effective mass, and they DO have SPIN.

I must second that. Under some circumstances holes are also considered as very interesting for applications as they can have pretty long spin coherence times and there are many groups working on that, especially in nanostructures. See "Optical pumping of a single hole spin in a quantum dot" by Brian Gerardot et al., Nature 451, 441 (2008) and references therein, if you are interested in hole spins in nanostructures.

 

[ZapperZ]

Holes definitely have spin. In high-Tc superconductors, the hole-doped compound have holes as the majority charge carrier, and they certainly possesses spin very much like electrons. Furthermore, in 1D Luttinger liquid material that are again hole-doped, the charge separation in such a system is the spinon-holon property.

Zz.

 

[stone]

Yes holes HAVE spin, just like they have mass or charge! Take a look at the following article
http://pubs.acs.org/doi/abs/10.1021/nl803440s
They actually measure the spin of the hole states.

 

[K^2]

To understand why the holes have spin, imagine a simplified picture with magnetic moment of a particle represented by a tiny current loop. Fill a region of space with magnetic moments all pointing in the same direction. Currents from neighboring loops effectively cancel each other out, except at the boundary, where surface current is formed. Now take out a magnetic moment from somewhere on the inside of the region. You end up with a boundary current there, which looks exactly like placing a particle with opposite magnetic moment there.

Similar argument can be made for angular momentum, but now, picture angular momentum as mass currents. The rest of the logic applies. So an electron "hole" will have the same magnetic moment and angular momentum as an electron. Ergo, it has the same spin, and in general behaves a lot like a loose positron.

 

[Goalie33]

Thanks guys! (or ladies, whatever.)

 

[Navy]

Yes, hole (missing electron) does have a spin. Consider a filled Fermi sea with all the electrons paired up so as to make zero total spin angular momentum. If one electron is elected out (say by photo emission) it creates a hole behind. As the electron has spin plus half the remaining hole must has minus half spin to conserve the total spin angular momentum.

 

[ZapperZ]

Yes, hole (missing electron) does have a spin. Consider a filled Fermi sea with all the electrons paired up so as to make zero total spin angular momentum. If one electron is elected out (say by photo emission) it creates a hole behind. As the electron has spin plus half the remaining hole must has minus half spin to conserve the total spin angular momentum.

Just so you know, since that was your first post here, you are responding to a thread that had its last activity in Jan. 2011.

Zz.