Hard Domains Domain Wall In The Uniform Rotation Model And Experimental Study Of Positive And Negative Vbl Model

The length (or diameter) of the three kinds of hard domains (ordinary hard bubble (OHB) the first kind of dumbbell (ID) the second kind of dumbbell( IID)) in garnet bubble films, and the length of the dumbbelIs(ID IID) in different direction of rotation are measured in detail under the variety bias field.It was first found that it was similar about the length of ordinary hard bubble (OHB), the first kind of dumbbell (ID) and the second kind of dumbbell ( IID) dependence of the bias field, they exist a character bias field (Hb)t, when Hb<(Hb)t, there was no rules about the length change under the variety bias field. The length change of domains under the bias field was independent of the number of VBLs in the hard domains; when Hb>(Hb)t, it was regular about the length change under the bias field, with the measurement of the collapse field, we find that the harder of the domain is, the longer the domain is. Thereby, we first found it rational of uniform-twist model experimentally, and also found that Hb>(Hb)t is the useful rang of uniform-twist model base on the experiment, and this is applicable for the three hard domains.Through the study about the length of these dumbbells(ID IID) in different rotation direction change with the bias field, we find that those dumbbells in same length have different static character because of the different rotation direction, it is very different of the collapse field in the clockwise and reverse rotation dumbbell domains. As for ID the stripe-to-bubble field of clockwise rotation dumbbell is lower than that reverse one, but the collapse field is just reverse For IID, the collapse field of clockwise rotation dumbbell is higher than that reverse one.It is suggesting that the phenomenon of the experiment is related to the existence of right or left-handed Bloch lines. And it first sustains the model experimentally.