Excerpt from the wikipedia page that summarizes the relevant experiments:

Published studies
The first formal studies using memory implantation were published in the early 1990s, the most famous being "The Formation of False Memories" (commonly referred to as the "Lost in the Mall" study) by Loftus and Pickrell.[1] The basic technique used in this study involved asking family members of a participant to provide narratives of events that happened when they were young and then add another event that definitely had not happened. The participants saw these four narratives and were told to try to remember as much as possible about each event. Across a number of studies using memory implantation, about 37% of people have come to remember parts of or entire events that never actually happened.[4]

Other studies have expanded on this paradigm by introducing photos instead of narratives. Wade and colleagues found that 50% of people came to remember details of a hot air balloon ride that never happened, after seeing a manipulated photo depicting the event.[5] Later it has been argued that photos by themselves do not produce more false memories than narratives, but that both methods have the power to successfully implant false memories.[6] Real photos have also been found to increase the creation of false memories. In a study by Lindsay and colleagues people were shown a childhood photo from the same time period as the false event. Seeing the photo resulted in more false memories, even when the photos did not depict the actual event.[7]

In a study with children 1999 Pezdek and Hodge found that it was easier to implant a memory of a plausible event (being lost in a mall) than an implausible one (receiving a rectal enema).[8] Later follow up studies, however, show that the perceived plausibility of a false event can be changed, making the false event easier to implant.[9][10] Taken together, these findings show that there are many factors that are important for the way people remember events.

Mazzoni et al. also suggest a model for the development of false memories through suggestions which model includes 3 processes.[10] The first process is to make people perceive the event as plausible, the second is to make people believe it is likely to have happened to them and the third step is to help people interpret thoughts and fantasies about the event as memories. Other factors influencing the likelihood of producing false memories include imagining the events and making a source-monitoring error, specifically reality monitoring.[11]

Legal case
A real life example of memory implantation occurred during the criminal case against Paul Ingram. Ingram was accused by his daughters of recurring sexual abuse in their childhood. Ingram denied all allegations at first but after being interviewed by police and therapists he came to remember multiple instances of abuse.

Sociologist Richard Ofshe considered this confession a result of suggestive questioning and decided to test his theory. He told Ingram about a made-up scenario and said it was another accusation made by his children. Ofshe asked Ingram to try and remember as much as possible about this new event. Ingram could not recall anything straight away but after thinking about it for some time came up with a written confession where he described in detail what had happened. His children confirmed to Ofshe that the event had never actually happened; Ingram had created an entirely false memory of an event after suggestions from Ofshe. Ofshe considered this successful memory implantation evidence of Paul Ingram's suggestibility and in his opinion it questions the accuracy of Ingram's other confessions.[12]

(https://en.wikipedia.org/wiki/Memory_implantation)