This video demonstrates how to play an A-Major arpeggio in open position, shifting the third of the chord (C#4) up semitone to D4 by striking the D while holding the rest of the chord. Sliding to D produces an A-sus4 chord, which returns to A-Major when the D is released, sliding back down to C#.
To reproduce this technique:
1) Play and hold E4, C#4, and A4, with the right hand pinky, middle finger, and thumb respectively.
2) Play D4 with the right hand ring finger. This step bends the C# to the D.
3) Release the ring finder from D4. This step bends the D back down to C#.