< p >你看< span class = " math-container " > \微分算符\ vec B美元< / span >漂移(口语:grad-E漂移)。< / p > < p >这种类型的运动可以解释在一个简化的方式,想象一个二维平面时,y = 0,分开两个不同的磁场强度,< span class = " math-container " >说是< / span >美元。Let us say that for y>0, $\rm B_z$ is large and for y<0, $\rm B_z$ is weak. The strong field imparts a small gyro-radius for the charged particles, while the weak field imparts a large gyro-radius. Positive and negative charges orbit in opposite directions in the field, hence along the field gradients, they tend to drift left and right. This type of drift therefore can lead to net charge separation, which results in an E-field, which again leads to $\rm \vec E\times \vec B$-drift, which is uniform in direction for both charges. This is somewhat illustrated in this lecture, part 2.3. There are other types of drift motions, but the aforementioned two are usually all covered in introductory lectures to plasma physics. Another good one is here.